出版者・発行元：Physical Review B  

DOI： 10.1103/PhysRevB.103.094428

Scopus

出版者・発行元：公益社団法人 日本金属学会  

<p>Ferromagnetic Mn–Al–C (τ-phase) can be synthesized by a single-route conventional reactive sintering method. The maximum magnetization and coercivity were 75.8 Am²/kg and 57 mT, respectively. The τ-phase fraction was evaluated to be 81 mass% for Mn₅₅Al₄₅C₂ annealed at 1273 K. The τ-phase of Mn₅₅Al₄₅C₂ can be synthesized at an annealing temperature from 873 to 1273 K, whereas that of Mn₅₅Al₄₅ cannot be synthesized. It was indicated that the phase stability of the hcp-phase (ε-phase) was improved by adding carbon, resulting in an ε–τ transformation.</p>

DOI： 10.2320/matertrans.MT-M2020166

Scopus

出版者・発行元：公益社団法人 日本金属学会  

<p>Combined accelerating effects of ε–τ phase transformation by in-magnetic-field annealing and Zn-addition were investigated for Mn₅₃Zn₂Al₄₅ in magnetic fields up to 15 T. The in-field annealing for Zn-added sample accelerated the ε–τ transformation 16 times faster than Mn₅₅Al₄₅ at annealing temperature of 623 K. The reduction of magnetization after finishing ε–τ transformation was also more rapid than that of Mn₅₅Al₄₅. However, magnetic-field-induced acceleration of ε–τ phase transformation and suppression of precipitation of β-phase were observed for Zn-added alloy Mn₅₃Zn₂Al₄₅ annealed at 573 K. The obtained results suggested that the β-phase stabilized against both τ- and ε-phases by Zn-addition. Therefore, although the ε–τ transformation was efficiently accelerated by in-field annealing of Mn₅₃Zn₂Al₄₅, more precisely control of annealing time is required for obtaining high fraction of ferromagnetic τ-phase.</p>

DOI： 10.2320/matertrans.MT-M2020235

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Alloys and Compounds  

In-field heat treatments of a solid-liquid Mn/Ga diffusion couple were conducted at 573 and 673 K with and without a magnetic field of 5 T to investigate magnetic field effects on the phase formation. Formation of the β-Mn, Mn3Ga, γ-MnGa, λ-MnGa, Mn2Ga5, and MnGa4 phases was observed. The obtained results indicated that the reaction and phase growth of λ-MnGa and Mn2Ga5 proceeded by diffusion-controlled process for both heat treatments at 0 and 5 T. We confirmed that a magnetic field suppressed the phase growth of λ-MnGa and Mn2Ga5. The parabolic coefficients of the λ-MnGa and Mn2Ga5 phases were exponentially suppressed by applying magnetic field of 5 T. It is suggested that gain of Zeeman energy of Mn-rich phase played a key role for the magnetic-field-induced suppression of the formation of the λ-MnGa and Mn2Ga5 phases.

DOI： 10.1016/j.jallcom.2021.161310

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Magnetism and Magnetic Materials  

A magnetic field enhanced the decomposition of a Cu2MnAl Heusler alloy. An aging treatment at 573 K under 10 T promoted decomposition of a L21 phase and hard magnetic properties were exhibited. The crystallite size of the L21 phase decreased on annealing over 12 h and approached 22 nm at zero field. However, the crystallite size of the L21 phase of the 5 T-annealed sample was almost half that of the 0-T-annealed sample and decreased rapidly, indicating enhanced grain refinement by in-field annealing. Decomposition of the L21 phase was more pronounced in the 10-T-aged sample. The hysteresis loop for 10-T-aged sample had a large coercive force of 232 mT and a magnetization of 13 Am2/kg. These properties were markedly different from those of the 0-T-annealed sample. An increase of nucleation owing to a decrease of critical radius caused grain refinement associated with decomposition and magnetic hardening of Cu2MnAl.

DOI： 10.1016/j.jmmm.2021.168411

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： https://doi.org/10.1016/j.physb.2020.412379

その他リンク： https://www.sciencedirect.com/science/article/pii/S0921452620303884

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： https://doi.org/10.1016/j.jallcom.2020.155193

その他リンク： https://www.sciencedirect.com/science/article/pii/S0925838820315565?via%3Dihub

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本金属学会  

The spin reorientation and Curie temperature of Mn21xFexSb11ySny (0 ¯ x, y ¯ 0.15) compound were investigated by magnetization measurements. Spin reorientation temperature increased from 255 K at x = 0 to 383 K at x = 0.15, whereas it almost unchanged by Sn substitution. Curie temperature decreased down to 518 K with both Fe and Sn substitution. Substitution of Fe stabilized the ferrimagnetic state with magnetic moment lying in c-plane. Substitution of Sn induced the antiferromagnetic phase at low temperature. It was found that the magnetic hysteresis derived from quasi first-order magnetic phase transition exhibited at x 2 0.10 or T 2 300 K.

DOI： 10.2320/matertrans.mt-mn2019016

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本金属学会  

Nitrogenation of Sm2Fe17 powder was performed under a zero field and a magnetic field of 5 T at 623, 673 and 743 K to clarify the magnetic field effect on nitrogenation. Applying a magnetic field of 5 T induced nitrogenation compared with zero-field nitrogenation, and almost fully nitride Sm2Fe17N2.9 was obtained at 743 K. Mössbauer spectroscopy results suggested that a 5-T magnetic field promoted the phase transformation to the fully-nitride Sm2Fe17N3 phase. The magnetic field effect was discussed based on the magnetic energy gain and magnetic properties of host Sm2Fe17 and fully nitride Sm2Fe17N3

DOI： 10.2320/matertrans.mt-mn2019012

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： https://doi.org/10.2320/matertrans.MT-MN2019015

その他リンク： https://www.jstage.jst.go.jp/article/matertrans/61/8/61_MT-MN2019015/_article

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： https://doi.org/10.2320/matertrans.MT-MN2019016

その他リンク： https://www.jstage.jst.go.jp/article/matertrans/61/8/61_MT-MN2019016/_article

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： https://doi.org/10.2320/matertrans.MT-MN2019011

その他リンク： https://www.jstage.jst.go.jp/article/matertrans/61/8/61_MT-MN2019011/_article

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： https://doi:10.2320/matertrans.MT-MN2019013

その他リンク： https://www.jstage.jst.go.jp/article/matertrans/61/8/61_MT-MN2019013/_article

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本金属学会  

DOI： https://doi.org/10.2320/materia.59.422

その他リンク： https://www.jstage.jst.go.jp/article/materia/59/8/59_422/_article/-char/ja/

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： doi:10.2320/matertrans.MT-MN2019012

その他リンク： https://www.jstage.jst.go.jp/article/matertrans/61/8/61_MT-MN2019012/_article

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本金属学会  

Pressure effects on magnetic susceptibility» and energy gap Eg0 of narrow-gap semiconductor FeSb2 were investigated for the temperature range of 50300 K and pressures up to 13 kbar. The estimated Eg0 for ambient pressure, Eg0(0), was 29 meV. By application of pressure,» was suppressed, and Eg0(P) was estimated to be 52 meV for 13 kbar. The fourth-order expansion coefficient £ of the free energy in magnetization was positive and enhanced by applying pressures.

DOI： 10.2320/matertrans.mt-mn2019015

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本金属学会  

The magnetization measurements were carried out for polycrystalline Au4V in magnetic fields up to 130 kOe. The spontaneous magnetic moment ps was determined to be 0.255 ®B/V at 4 K by high field magnetization. The magnetization process was analyzed on the basis of Takahashi’s spin fluctuation theory for weak itinerant electron ferromagnets. The characteristic parameters of the spin fluctuation were estimated to be TA = 1.3 © 103 K and T0 = 2.3 © 103 K using the data for 110130 kOe.

DOI： 10.2320/matertrans.mt-mn2019011

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： https://doi.org/10.2355/isijinternational.ISIJINT-2019-470

その他リンク： https://www.jstage.jst.go.jp/article/isijinternational/60/4/60_ISIJINT-2019-470/_article

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： https://doi.org/10.1016/j.jmmm.2019.166199

その他リンク： https://www.sciencedirect.com/science/article/pii/S030488531933389X

出版者・発行元：一般社団法人 日本鉄鋼協会  

<p>The effect of magnetic fields on solid-liquid reactions in the Fe–Ga binary system was investigated using Fe/Ga diffusion couples. The reaction and phase growth proceeded by diffusion-controlled process for both 0 and 10 T. It is found that the growth of the intermetallic phases was suppressed by magnetic fields of 10 T regardless of whether <i>α</i>-Fe was in a ferromagnetic or paramagnetic state. The pre-exponential factors in the parabolic coefficient of the Fe₃Ga + eutectic region at 0 and 10 T were 2.50 × 10⁴ m²/s and 1.32 × 10³ m²/s, respectively. Meanwhile, activation energies at 0 and 10 T were 336 kJ/mol and 318 kJ/mol, respectively, which indicated the ineffectiveness of magnetic fields. That is, reduction of pre-exponential factor of the parabolic coefficient leads the magnetic-field-induced suppression of the reaction in Fe/Ga.</p>

DOI： 10.2355/isijinternational.ISIJINT-2019-470

Scopus

記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

DOI： http://hdl.handle.net/10232/00030849

その他リンク： http://hdl.handle.net/10232/00030849

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： https://doi.org/10.1063/1.5043069

その他リンク： https://aip.scitation.org/doi/full/10.1063/1.5043069

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： https://doi.org/10.1063/1.5043105

その他リンク： https://aip.scitation.org/doi/full/10.1063/1.5043105

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： https://doi.org/10.1063/1.5042834

その他リンク： https://aip.scitation.org/doi/full/10.1063/1.5042834

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

出版者・発行元：Metals  

DOI： 10.3390/met7090364

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1109/LMAG.2016.2616843

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

出版者・発行元：IEEE Magnetics Letters  

DOI： 10.1109/LMAG.2016.2617859

Scopus

出版者・発行元：IEEE Magnetics Letters  

DOI： 10.1109/LMAG.2017.2687878

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）  

記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.4961338

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2320/matertrans.M2015382

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2320/jinstmet.J2015055

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jmmm.2015.07.114

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：AIP Conference Proceedings  

Structural, magnetic and thermal properties of ferromagnetic MnCo1-xFexGe (0 ≤ x ≤ 0.12) compounds were investigated. The Curie temperature TC and the martensitic transformation temperature TM of MnCoGe (x = 0) were determined to be 340 K and 510 K, respectively. With increasing x from 0 to 0.08, TM decreased and reached room temperature (290 K) for x ∼ 0.08. For x > 0.09, MnCo1-x Fex Ge did not exhibit the martensitic transformation. The compound for x ∼ 0.08 showed a first-order magnetic transition with a thermal hysteresis of 20 K and was accompanied by the martensitic transformation in the vicinity of room temperature. The phase diagram of MnCo1-x Fex Ge (0 ≤ x ≤ 0.12) is presented.

DOI： 10.1063/1.4961336

Web of Science

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1016/j.phpro.2015.12.126

記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）  

その他リンク： http://hdl.handle.net/10232/26366

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）  

その他リンク： http://hdl.handle.net/10232/26364

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1016/j.phpro.2015.12.148

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（大学，研究機関等紀要）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本金属学会  

We applied first-principles total-energy calculations to several compounds Mn2-xMxSb (M = Ti, Cr, Co, or Cu) to calculate the total energy. The results indicate that the Ti and Cu (Cr and Co) atoms prefer the Mn(II) site to the Mn(I) site [Mn(I) to Mn(II)]. These results are consistent with experimental observations. The antiferromagnetism (AF) [ferrimagnetism (FR)] is more stable than FR (AF) upon decreasing (increasing) the distance between the Mn(II) and Sb atoms in the z direction in all Mn2-xMxSb systems. This result indicates that the environment around the Mn atom plays a very important role in the stabilization of the AF state, as is the case with Mn2Sb1-xAsx systems. For Mn2-xCoxSb systems, the atomic disorder between the Mn and Co atoms is insensitive to the relative stability of two magnetic phases AF and FR.

DOI： 10.2320/matertrans.m2014417

Web of Science

Scopus

記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語  

DOI： 10.7566/JPSCP.3.011003

記述言語：日本語   出版者・発行元：日本熱測定学会  

DOI： 10.11311/jscta.41.2_43

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本金属学会  

The electronic and magnetic properties of Mn2Sb1-xAsx (where x = 0, 0.5, 1) are investigated from first-principles total-energy calculations. The predicted magnetic ground states (ferrimagnetism for x = 0 and antiferromagnetism for x = 1) are in agreement with experimental observations; however, this is not the case for x = 0.5. Here, it is found that the artificial change of the surrounding atoms of Mn stabilizes the antiferromagnetism. A similar change stabilizes ferrimagnetism (antiferromagnetism) for x = 1 (x = 0). These results indicate that the environment around the Mn atoms plays a very important role in the stabilization of antiferromagnetism in the Mn2Sb1-xAsx system. In addition, an analysis of the sign of an effective exchange interaction as a function of the distance between the Mn atoms is performed.

DOI： 10.2320/matertrans.m2014251

Web of Science

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：2014 10th International Vacuum Electron Sources Conference, IVESC 2014 and 2nd International Conference on Emission Electronics, ICEE 2014 - Proceedings  

We investigated the structural properties and electrical characteristics of GdTiO3 dielectrics for IGZO TFT devices. We used XRD, XPS, and AFM to examine the structural, compositional, and morphological features of the GdTiO3 film, respectively. The IGZO TFT featuring a GdTiO3 gate dielectric exhibited a large field-effect mobility of 32.3 cm2/V-s, a small threshold voltage of 0.14 V, a high Ion/Ioff current ratio of 4.2 × 108, and a low subthreshold swing of 213 mV/decade.

DOI： 10.1109/IVESC.2014.6891962

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本金属学会  

The structural and magnetic properties of Heusler alloy Ni 46Mn41In13 were studied by magnetization and X-ray powder diffraction measurements in the 4.5350K temperature range and in magnetic fields up to 5 T. The alloy undergoes martensitic transformation from a L21-type cubic structure with ac = 0.600nm at 293K to a six-layered monoclinic (6M) structure in the transition temperature of 160230 K. The lattice parameters for the 6M structure were estimated to be am = 0.441 nm, bm = 0.557 nm, cm = 1.30 nm, αm = 90.0°, βm = 94.0°, and γm = 90.0° at 75 K. In this transformation from the L21 to 6M structures, the cell volume contracts by 0.34% at 8K. In addition, we observed the magnetic field-induced reverse transformation of this alloy. © 2014 The Japan Institute of Metals and Materials.

DOI： 10.2320/matertrans.m2013372

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：AIP Conference Proceedings  

The magnetic field effect (MFE) on liquidus boundary of Bi-Mn binary system was investigated by differential thermal analysis (DTA) and the computer coupling of phase diagram method (CALPHAD). The liquidus boundary for Bi-18at.%Mn and Bi-24at.%Mn rose clearly by the application of the magnetic fields. The MFE for liquidus boundary temperature Tliq changed from ΔTliq∞B2 to ΔTliq∞B because of the large increase of the peritectic temperature from BiMn and BiMn1.08 by the application of magnetic field.

DOI： 10.1063/1.4897725

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the Korean Physical Society  

Magnetization and electrical resistivity measurements were carried out for polycrystalline Mn2Sb1-xGex (0.05 ≤ x ≤ 0.2) in magnetic fields up to 16 T in the 4.2 - 600 K temperature range in order to investigate the magnetic and the electrical properties under high magnetic fields. Mn2Sb0.92Ge0.08 showed a Curie temperature, T C, of 532 K and a first order magnetic transition from a ferrimagnetic (FRI) to an antiferromagnetic (AFM) phase at T t = 230 K with decreasing temperature in a zero magnetic field. With increasing x, T C decreased and T t increased. For Mn2Sb0.92Ge0.08, a matamagnetic transition from an AFM to a FRI phase was observed at 215 K. The magnetic phase diagram of Mn2Sb1-xGex is presented. © 2013 The Korean Physical Society.

DOI： 10.3938/jkps.63.747

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本金属学会  

First-principles total-energy calculations have been performed for the hypothetical case of x = 1 in Mn2-xXxSb (X = Co and Cu) for several magnetic states using the full-potential linearized augmented plane wave method based on the generalized gradient approximation. The calculated total energy indicates that the Co (Cu) atom prefers the site Mn(I) to the site Mn(II) (Mn(II) to Mn(I)). This result of Co is consistent with the available neutron diffraction experiment. For CoMnSb where Co occupies the site Mn(I) the change of lattice constants (a and c) and c/a from AF2 to F is in good agreement with experimental trends. Our results indicate that the optimization of the ratio c/a (lattice distortion) is crucial to determine the most stable magnetic state and that the optimization of the atomic positions of the sites Mn(II) and Sb is also crucial. © 2013 The Japan Society for Technology of Plasticity.

DOI： 10.2320/matertrans.m2013327

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記述言語：日本語   掲載種別：研究論文（大学，研究機関等紀要）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本磁気学会  

DOI： 10.3379/msjmag.1305r007

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本金属学会  

Magnetization, electrical resistivity and X-ray diffraction measurements were carried out for Mn1.8Co0.2Sb with a tetragonal structure in 4.2 ≤ T ≤ 280K and in field B up to 16 T. For B = 0 T, anisotropic structural deformation occurred at Tt ∼ 140K for zero-field cooling (ZFC), accompanied by a first-order magnetic transition from the ferrimagnetic (FRI) to antiferromagnetic (AFM) phases. In this deformation, the lattice parameters a and c changed by δ a/a=+0.15% and by δ c/c = -0.44%, respectively. By applying magnetic fields of 5 T, Tt decreased to 60K with thermal hysteresis of 35 K. The two-phase coexistence of the AFM and residual FRI phases was observed even at 10K for field cooling of 5 T, while a single phase of AFM was confirmed for ZFC. At B = 16 T, the transition did not occurs. In addition, a field-induced structural deformation was observed, accompanied by the metamagnetic transition just below Tt. The obtained results are discussed from a viewpoint on entropy change for the transition. © 2013 The Japan Institute of Metals and Materials.

DOI： 10.2320/matertrans.m2012415

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Magnetism and Magnetic Materials  

We have demonstrated the effect of pressure on the steplike metamagnetic transition and its associated magnetostriction in (Eu 1-xGd x) 0.6Sr 0.4MnO 3 (x=0 and 0.1). The critical field initiating the field induced ferromagnetic transition in both samples is lowered by the applied pressure. The further application of external pressure up to 1.2 GPa on the x=0 parent sample causes a spontaneous ferromagnetic transition with a second-order like character, leading to collapses of the steplike transition and its concomitant lattice striction. These findings indicate a crucial role of the low-temperature phase separated state characterized by a suppressed magnetization upon decreasing temperature. © 2012 Elsevier B.V.

DOI： 10.1016/j.jmmm.2012.06.036

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Journal of Physics: Conference Series  

α-Dy2S3 possesses orthorhombic crystal structure having two crystallograpically inequivalent Dy sites. Magnetization process of α-Dy2S3 single crystal after cooling in the high magnetic field of 18 T has been investigated. The magnetization under the field of 18 T along the α-axis on the cooling process from 150 K shows step-like rises at 70 and 40 K and reaches about 9 μB per one Dy3+ at 1.5 K. This value, which corresponds to 90 % of full saturation moment of Dy3+, is much larger than 6 μB obtained at the same conditions after cooling in no magnetic field (zero-field cooling; ZFC). After cooling to 1.5 K, the magnetization while decreasing field shows abrupt drops at 3.0 and 1.7 T, and then comes to 0 μB at 0 T. Subsequently, while increasing field, the magnetization demonstrates a similar curve to that obtained after ZFC without step-like rise below 13.1 T. At μ0H = 13.1 T, the magnetization rises suddenly and agrees with the curve for the decreasing process. This irreversible magnetization process yields extremely broad hysteresis having width of μ0ΔH = 11.4 T. Broader hysteresis and narrower one are also observed at 4.2 and 10 K, respectively.

DOI： 10.1088/1742-6596/400/3/032010

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：公益社団法人 日本金属学会  

Measurements of magnetization, electrical resistivity and high field X-ray powder diffraction (XRD) were carried out for polycrystalline Mn 1.8Co 0.2Sb in magnetic fields up to 5 T in 4.2-300 K temperature range, in order to investigate the structural properties affected by magnetic fields. In a zero field, the compound shows the first-order magnetic transition from the ferrimagnetic (FRI) to antiferromagnetic (AFM) states at T t = 145 K with decreasing temperature. By applying magnetic fields of 5 T, T tdecreased to 60 K with thermal hysteresis of 35 K. From the XRD measurements, not only the AFM phase but also the residual FRI phase was confirmed even at 10 K in cooling process under 5 T. Results obtained indicate that the residual FRI phase is kinetically arrested. © 2012 The Japan Institute of Metals.

DOI： 10.2320/jinstmet.76.246

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（その他学術会議資料等）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Magnetism and Magnetic Materials  

We studied temperature and magnetic field dependence of magnetization, M(T) and M(B), on thiospinel FeCr2S4. We observed a step-like anomaly at TOO∼9K for M(T) attributed to an orbital order transition in magnetic field 0 <B≤7T. Furthermore, also for M(B), the step-like anomaly appears at Bc∼5.5T below TOO. This suggests an existence of a magnetic phase boundary at Bc in T<TOO. Because the anomaly at Bc of M(B) exists in the orbital ordered phase, the spin structure of FeCr2S4 in T<TOO is strongly coupled with the lattice of the system. © 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jmmm.2011.07.041

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Alloys and Compounds  

Martensitic transformation in a highly ordered Fe3Pt has been investigated by magnetization and X-ray diffraction measurements. We confirmed that a new type of face-centered tetragonal (FCT) martensite phase appears below 60 K in Fe3Pt with a degree of order S = 0.88. The tetragonality c/a gradually increases with decreasing temperature, and is approximately 1.005 at 10 K. This is in contrast to the tetragonality c/a < 1 generally observed in the FCT martensite with a degree of order less than 0.8. The spontaneous magnetization increases in association with the transformation. © 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jallcom.2011.06.035

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PHYSICAL SOC JAPAN  

Ferromagnetic shape memory effects of antiperovskite Mn3CuN are markedly altered by nitrogen deficiency. The martensitic transformation occurs at a lower temperature than ferromagnetic ordering for nitrogen-deficient Mn3CuN0.8, although they both occur simultaneously for stoichiometric Mn3CuN. In the martensitic phase, Mn3CuN0.8 contracts in a direction parallel to the magnetic field, in contrast to the expansion observed in Mn3CuN, implying that the easy axis is converted from the longer a axis in Mn3CuN to the shorter c axis in Mn3CuN0.8. The operating magnetic field for magnetostriction drastically decreases for Mn3CuN0.8, suggesting a possible supermagnetostriction around the critical compositional region for the easy-axis conversion.

DOI： 10.1143/JPSJ.79.073706

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Elsevier B.V.  

We have investigated martensitic transformation in a highly ordered Fe 3Pt by X-ray diffraction measurements. We found that a new type of FCT martensite phase appears in Fe3Pt with degree of order S = 0.88. In this martensite phase, the tetragonality c/a of the martensite is approximately 1.005 at 10 K, being different from that of so far known FCT martensite phase with c/a &lt
1.

DOI： 10.1016/j.phpro.2010.11.085

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

Study of magnetostriction of (Lu(0.8)Ce(0.2))(2)Fe(17) has been performed by two methods, bulk and microscopic: by the capacitor dilatometer on a single crystal grown by the Czochralski method and by the X-ray powder diffraction. The field-induced transition from the antiferromagnetic to the ferromagnetic state is accompanied by the lattice expansion both in the basal plane and along the c-axis of the hexagonal structure. In addition to the spontaneous linear magnetostriction lambda(s)(a) = 0.8 x 10(-3), lambda(s)(c) = 6.8 x 10(-3) along the a and c axes, respectively, and volume effect omega(s) = 8.4 x 10(-3), a comparable field-induced magnetostriction (lambda(a) = 1.3 x 10(-3), lambda(c) = 3.4 x 10(-3), omega = 6.0 x 10(-3)) is observed in a field of 5T applied along the a-axis. (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jallcom.2008.11.003

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

The ab -plane infrared and optical reflectance of single-crystal Bi2 Sr2 CoO6+δ (0.4&lt;δ&lt;0.5) have been measured over a wide frequency range (50-55000 cm-1) and at temperatures between 20 and 330 K. The room-temperature infrared spectrum displays an insulating characteristic. The optical gap determined from the infrared conductivity (∼0.53 eV) is consistent with thermal activation energy from dc transport measurements. Upon passing through the 265 K antiferromagnetic ordering transition, a softening of the phonon mode near 205 cm-1 correlates well with the temperature-dependent normalized square of the sublattice magnetization. Furthermore, the magnetic-order-induced splitting of the phonon modes at about 238 and 376 cm-1 is observed. Additionally, the phonon mode at about 588 cm-1 exhibits a Fano-type line shape. Since no appreciable structural change was detected at low temperatures in x-ray diffraction studies, all of these observables suggest a complex nature of spin-phonon coupling in this material. © 2009 The American Physical Society.

DOI： 10.1103/PhysRevB.79.155109

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER INST PHYSICS  

We report a significant decrease in the low-temperature resistance induced by the application of an electric current on the ab-plane in the paramagnetic insulating (PMI) state of (La0.4Pr0.6)(1.2)Sr1.8Mn2O7. A colossal electroresistance effect attaining -95% is observed at lower temperatures. A colossal magnetoresistive step appears near 5 T at low temperatures below 10 K, accompanied by an ultrasharp width of the insulator-metal transition. Injection of higher currents to the crystal and magnetic field cooling process cause a disappearance of the steplike transition. These findings have a close relationship with the presence of the short-range charge-ordered clusters pinned within the PMI matrix of the crystal studied.

DOI： 10.1063/1.3095598

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：NATL INST MATERIALS SCIENCE  

A system was developed measuring x-ray powder diffraction in high magnetic fields up to 5 T and at temperatures from 283 to 473 K. The stability of the temperature is within 1K over 6 h. In order to examine the ability of the system, the high-field x-ray diffraction measurements were carried out for Si and a Ni-based ferromagnetic shape-memory alloy. The results show that the x-ray powder diffraction measurements in high magnetic fields and at high temperatures are useful for materials research.

DOI： 10.1088/1468-6996/10/1/014612

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPAN INST METALS  

X-ray powder diffraction, magnetization measurements, and differential thermal analysis (DTA) of polycrystalline MnBi were carried out in zero magnetic field as will as in magnetic fields of up to 14 T and in the temperatures range of 300-773 K, in order to investigate magnetic phase transition. In zero magnetic field, a magnetic phase transition from ferromagnetic to paramagnetic state is exhibited at temperature (T-t) of 628 K, accompanied by decomposition. With increasing magnetic field up to 14 T, T-t increases linearly with the rate of 2 KT-1. A metamagnetic transition between the paramagnetic and field-induced ferromagnetic states was observed just above T-t The exothermic and endothermic peaks were detected in the magnetic field dependence of DTA signals in the interval of 626-623 K, which relates to the metamagnetic transition. The obtained results are discussed on the basis of a mean field theory.

DOI： 10.2320/jinstmet.73.40

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IOP PUBLISHING LTD  

We report the pressure effect on a steplike magnetostriction of single crystalline (La0.4Pr0.6)(1.2)Sr(1.8)Mb(2)O(7) bilayered manganite, for our understandings of the ultrasharp nature of the field-induced first-order transition from a paramagnetic insulator and to a ferromagnetic metal phase. Application of pressure suppresses a steplike transformation and causes a broad change in the magnetostriction. A delocalization of carriers is promoted with the applied pressure, resulting in the suppressed steplike behaviour. The steplike behaviour observed is closely related to the existence of localized carriers.

DOI： 10.1088/1742-6596/150/4/042121

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IOP PUBLISHING LTD  

We have performed the specific heat and the electrical resistivity measurements under high magnetic fields for Heusler compounds Ru2CrGe and Ru2CrSn. We found that the electrical resistivity for Ru2CrGe shows an upturn in the vicinity of 130 K and changes a metallic to a semiconducting-like behavior with decreasing temperature. By applying magnetic field, a negative magnetoresistance was observed below 200 K. On the other hand, the electrical resistivity for Ru2CrSn shows a semimetallic-like behavior. The results of the electrical resistivity in Ru2CrGe suggest that the compound has a gap-like structure in the electronic structure at the Fermi level. Moreover, it was found that another phase transition occurs in Ru2CrGe and Ru2CrSn, in addition to the magnetic transition.

DOI： 10.1088/1742-6596/150/4/042153

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Rare earth sesquisulfides α-Tb2S3 and α-Dy2S3 possess orthorhombic crystal structure having two independent rare earth sites. High field magnetization processes for single crystals of these compounds have been investigated up to μoH 18 T. Some step-like transitions have been observed in both compounds. The magnetization of α-Tb2S3 single crystal under the field along the 6-axis at T 1.4 K shows a steep increase of about 4.5 μB, which corresponds to a half of full saturation moment of free Tb3+, at μoH 2.2 T. It is considered that the reorientation of Tb3+ moments on only one Tb site into a ferromagnetic arrangement occurs. When the magnetic field is perpendicular to the b-axis, one-step transition at μoH 0.7 T for Hc and two-step transitions at 0.7 and 1.2 T for Ha are observed. As for α-Dy 2S3, the magnetization curve at T 1.5 K shows two-step transitions at 1.3 and 1.6 T (Hb), three or four dull steps (Ha or c). The total height of two steps in the M-H curve for Hb corresponds to a half of full Dy3+ moment. © 2009 IOP Publishing Ltd.

DOI： 10.1088/1742-6596/150/4/042027

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IOP PUBLISHING LTD  

The positive hyperfine field at Co nucleus in a Heusler alloy Co2TiGa is discussed to be not dominated by the orbital hyperfine field from a quite different point of view from former studies. Field-induced-moment nuclear coupling for Co-59 via spin-orbit interaction on Co atom in Co2TiGa is discussed to be small from the observed high-field shift of the NMR of Co-59 in the ferromagnetic state of only +0.83 % in contrast to the case of CoCl2 center dot 2H(2)O with +29%.

DOI： 10.1088/1742-6596/150/4/042037

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：IOP PUBLISHING LTD  

The magnetostriction and magnetoresistance associated with the field-induced and spontaneous first-order antiferro-ferromagnetic (AF-F) phase transitions have been studied for quasi-single-crystalline samples of La(0.25)Sm(0.75)Mn(2)Si(2), La(0.25)Y(0.75)Mn(2)Si(2) and La(0.27)Y(0.73)Mn(2)Si(2) compounds with natural layered ThCr(2)Si(2)-type structure. It was found that both the spontaneous and field-induced AF-F transitions are accompanied by a large volume magnetostriction Delta V/V approximate to 2 x 10(-3) and anisotropic linear changes of the lattice parameters Delta a/a approximate to 1.6 x 10(-3), Delta c/c approximate to -0.75 x 10(-3). The field-induced AF-F magnetic phase transition has been observed in magnetic fields applied both along the c-axis and in the basal plane, and the magnetostriction value is virtually independent of the direction of applied field. It has been found also that the magnetoresistance is positive in these compounds (the value of the electrical resistance in the ferromagnetic state is higher than that in the antiferromagnetic state) for the fields applied both along the c-axis and in the basal plane. The value of the magnetoresistance observed along the c-axis is 30 times as high as that in the basal plane. The obtained results indicate that the electronic band structure changes are likely responsible for the AF-F magnetic phase transitions observed in the RMn(2)X(2) compounds.

DOI： 10.1088/0953-8984/20/44/445219

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER PHYSICAL SOC  

We report the effect of pressure on the steplike magnetostriction of single crystalline bilayered manganite (La(0.4)Pr(0.6))(1.2)Sr(1.8)Mn(2)O(7), for our understanding of the ultrasharp nature of the field-induced first-order transition from a paramagnetic insulator to a ferromagnetic metal phase. The application of pressure suppresses a steplike transformation and causes a broad change in the magnetostriction. The injection of an electric current to the crystal also weakens the steplike variation in both the magnetostriction and magnetoresistance. The stabilization of ferromagnetic interaction or the delocalization of charge carriers is promoted with the applied pressure or applied current, resulting in the suppressed steplike behavior. Our findings suggest that the step phenomenon is closely related to the existence of localized carriers such as the short-range charge-orbital-ordered clusters.

DOI： 10.1103/PhysRevB.78.132411

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER PHYSICAL SOC  

We report the electric conductivity of three-dimensional (3D) nanoporous gold at low temperatures and in strong magnetic fields. It was found that topologically disordered 3D nanoporosity leads to extremely low magnetoresistance and anomalous temperature dependence as the characteristic length of nanoporous gold is tuned to be similar to 14 nm. This study underscores the importance of 3D topology of a nanostructure on electronic transport properties and has implications in manipulating electron transport by tailoring 3D nanostructures.

DOI： 10.1103/PhysRevLett.101.166601

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

The concentration evolution of crystal structure, magnetic moment and anisotropy constants in U-2(Fe1-xNix)(13.6)Si-3.4 investigated on single crystals grown by the Czochralski method is found to be similar to that in the previously studied U-2(Fe1-xNix)(13.6)Si-3.4 system, only the Ni solubility is limited by x = 0.3 in difference with unlimited Co solubility. (c) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jallcom.2007.06.086

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER HEIDELBERG  

The magnetostructural phase transformation and shape memory effect (SME) of Fe-added Ni(2)MnGa films were investigated. The free-standing films were heat-treated at 1073 K for 3.6 ks and constraint-aged (CA) at various conditions (473 similar to 723 K, 0 similar to 14.4 ks) to make the two-way SME. The reversible two-way SME by the temperature change was confirmed through the martensitic transformation (MT) and its reversion. The gradient of strain-temperature curve, the effective recovery strain and the width of thermal hysteresis were dependent on the CA conditions. The magnetic field (MF) induced structural phase transformation was evaluated by an XRD apparatus in high MF up to 5 T. It was confirmed that the martensitic phase was stabilized by the MF. Furthermore, the SME by the MF was observed around MT temperature on cooling process for the CA film. It was concluded that the MF induced SME appeared by the induction of the MT with MF.

DOI： 10.1140/epjst/e2008-00672-4

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PHYSICAL SOC JAPAN  

High-field electron spin resonance (ESR) measurements of single crystals of (CH3)(2)NH2CuCl3 (DMACuCl(3)) have been performed in the frequency range of 50 to 550 GHz in the paramagnetic region. In addition to the electron paramagnetic resonance, we have observed four ESR modes omega(1), omega(2), omega(3), and omega(4). The modes omega(2) and omega(3) have a frequency gap of 325 GHz (15.6 K), while the mode omega(1) has a gap of 420 GHz (20 K) at 0 T. The modes omega(2) and omega(3) are attributed to the transitions between the singlet and the triplet of the antiferromagnetic (AF) dimer. We found that the large spin-gap for the AF dimer still remains at the critical field B-c2 = 3.5 T determined by magnetization and specific heat measurements.

DOI： 10.1143/JPSJ.76.113704

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

The Sm-based filled skutterudite phosphides SmT4 P12 (T = Fe, Ru, Os) have been studied by 31P-NMR (nuclear magnetic resonance) and μSR (muon spin relaxation). The ferromagnetic order and the heavy fermion behavior in SmFe4 P12 and the antiferromagnetic order in SmOs4 P12 were confirmed by 31P-NMR and μSR. In SmRu4 P12, a successive anomaly around the metal-insulator transition temperature and around the Néel temperature was observed by 31P-NMR in high applied magnetic fields. The μSR results of SmRu4 P12 indicate the magnetic order below the metal-insulator transition temperature, which supports the existence of the octupolar order in SmRu4 P12. © 2007.

DOI： 10.1016/j.jpcs.2007.08.033

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Field and temperature dependencies of the magnetization measured along the principal axes of a U2Co15Si2 single crystal show that this compound is a ferromagnet with a spontaneous magnetic moment of 14.8 mu(B) per formula unit (at 4.2 K), located in the basal plane of the hexagonal crystal structure. A strong easy-plane magnetic anisotropy (K-1 = -0.97 MJ m(-3) at 4.2 K) is attributed to the U sublattice because Lu2Co15Si2 exhibits easy-axis anisotropy with K-1 = 0.42 MJ m(-3). The easy-plane anisotropy of U2Co15Si2 transforms to a cone of easy axes above 270 K. The magnetization vector approaches the c-axis at 350 K, and the compound has easy c-axis anisotropy up to the Curie temperature T-C = 601 K. (C) 2007 Published by Elsevier B.V.

DOI： 10.1016/j.jmmm.2007.03.006

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPAN INST METALS  

Magnetization measurements of polycrystalline MnBi were carried out in magnetic fields up to 10 T and in the temperature range from 300 to 773 K, in order to clarify the magnetic properties under high magnetic fields and high temperature. The magnetic phase transition temperature (T-c) at a zero magnetic field is 633 K, which almost linearly increases by 2.3 KT-1 with increasing fields up to 10 T. Furthermore, a metamagnetic transition was observed just above T, indicating that the phase transition is first order. The magnetic entropy change is estimated to be 14 J kg(-1) K-1 for 2 T at T-c using Clausius-Clapayron's equation, which is almost constant for magnetic fields up to 10 T.

DOI： 10.2320/jinstmet.71.489

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMERICAN PHYSICAL SOC  

We report a steplike lattice transformation of single crystalline (La0.4Pr0.6)(1.2)Sr1.8Mn2O7 bilayered manganite accompanied by both magnetization and magnetoresistive jumps, and examine the ultrasharp nature of the field-induced first-order transition from a paramagnetic insulator to a ferromagnetic metal phase accompanied by a huge decrease in resistance. Our findings support that the abrupt magnetostriction is closely related to an orbital frustration existing in the inhomogeneous paramagnetic insulating phase rather than a martensitic scenario between competing two phases.

DOI： 10.1103/PhysRevLett.98.267204

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：IOP PUBLISHING LTD  

UGe2 is a ferromagnetic heavy-fermion (HF) superconductor, which provides superconductivity under pressure in the range of 1.0 to 1.5 GPa. In this paper, we conducted detailed magnetization experiments up to 27 T and at atmospheric pressure. Magnetization along the a-axis indicates typical ferromagnetic property. On the other hand, magnetization along the b-axis is quite a bit smaller than that of the easy a-axis. The magnetocrystalline anisotropy constant is the same as the rare earth ferromagnet Nd2Fe17, which indicates that UGe2 is a highly anisotropic ferromagnet.

DOI： 10.1088/0031-8949/75/4/030

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER  

For CuGeO3 single crystals doped with 1% of Fe, the quantum critical behavior in a wide temperature range 1-40 K is reported. The critical exponents for susceptibility along different crystallographic axes are determined: alpha = 0.34 (B parallel to a and B parallel to c) and alpha = 0.31 (B parallel to b). The description of the temperature dependencies of the line width and g-factor could be obtained in the Oshikawa-Affleck theory assuming that staggered component of the magnetic moment is located predominantly along b-axis. Possible arguments favoring the competition between effects of the staggered field and antiferromagnetic ordering are provided.

DOI： 10.1007/s10948-006-0214-3

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMERICAN PHYSICAL SOC  

We have studied the pressure effect on magnetostriction, both in the ab plane and along the c axis of a (La, Pr)(1.2)Sr1.8Mn2O7 bilayered manganite single crystal over the temperature region where the field-induced ferromagnetic metal (FMM) transition takes place. For comparison, we have also examined the pressure dependence of magnetization curves at the corresponding temperatures. The applied pressure reduces the critical field of the FMM transition and it enhances the remanent magnetostriction. An anomalous pressure effect on the remanent lattice relaxation is observed and is similar to the pressure effect on the remanent magnetization along the c axis. These findings are understood from the viewpoint that the double-exchange interaction-driven FMM state is strengthened by the application of pressure.

DOI： 10.1103/PhysRevB.75.014427

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Substitution of Y for U in the itinerant 5f-electron metamagnet UCoAl transforms the system to a ferromagnetic ground state. Application of external hydrostatic pressure above 0.3 GPa suppresses the ferromagnetism and restores the &quot;UCoAl-type&quot; metamagnetism. However, the metamagnetic transition becomes of the second-order type instead of the first-order one for the parent UCoAl. © 2007 The Physical Society of Japan.

DOI： 10.1143/JPSJS.76SA.43

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Lu2Fe17 is a ferromagnet below TC∼140 K and antiferromagnet up to TN=275 K. Hydrogen absorption leads to a stabilization of the ferromagnetism over the whole range of magnetic order and to an increase of the ordering temperature up to TC=354 K in Lu 2Fe17H. The external pressure compensates the lattice expansion upon hydrogenation, and a reentrance of antiferromagnetism is observed. © 2007 The Physical Society of Japan.

DOI： 10.1143/JPSJS.76SA.82

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Magnetooptical measurements have been performed on the organic conductor β″ -(BEDT-TTF)(TCNQ) (x=0 salt), and a related compound, β″ -(BEDT-TTF)(TCNQ) 0.95 (F1-TCNQ) 0.05 (x=0.05 salt), to investigate their low-temperature Fermi surfaces (FSs). Although the room-temperature FS of both salts can be considered the same, our results indicate that the low-temperature FSs are completely different from each other. In the x=0 salt, the low-temperature FS consists of two very anisotropic quasi-two-dimensional (Q2D) FSs. Cross-sectional areas of anisotropic Q2D-FSs are very small, and correspond to 1-2 % of the first Brillouin zone at room temperature. On the other hand, in the x=0.05 salt, only a pair of quasi-one-dimensional FSs exist at low temperature. Compared with the band calculation of x=0 salt, this Q1D-FS originates from the BEDT-TTF conducting layers. This result indicates that the two hump-like anomalies in the temperature dependence of resistivity at 80 and 20 K, which are observed only in the x=0 salt, are related to the nesting of BEDT-TTF Q1D-FS. Hence, it is considered that anisotropic Q2D-FS pockets observed in the x=0 salt are generated by the imperfect nesting of Q1D-FS, and the density wave state may be formed in the x=0 salt at low temperatures. © 2007 The American Physical Society.

DOI： 10.1103/PhysRevB.75.045126

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PHYSICAL SOC JAPAN  

The P-31-NMR (nuclear magnetic resonance) measurements of the filled skutterudite SmRu4P12 have been carried out in several applied magnetic fields. The line width of the P-31-NMR spectrum rapidly increases below the metal-insulator transition temperature T-MI, which indicates the appearance of an internal field below the temperature. Though no distinct anomaly was observed below T-MI in low fields, a complicated structure was observed between the Neel temperature T-N and T-MI (T-N &lt; T-MI) above 70 kOe. The spin-lattice relaxation rate l/T-1 is almost independent of temperature above T-MI, and rapidly decreases below T-MI. The l/(T1) in low fields decreases monotonously, whereas the strong suppression of l/(T1) occurs between T-N and T-MI above 70 kOe. The structure of the spectra and the suppression of l/T-1 become apparent with increasing field.

DOI： 10.1143/JPSJ.75.124712

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

A discontinuity in the temperature dependence of the lattice parameters while preserving the crystal symmetry was observed for TbPdAl, TbNiAl and TbPd0.9Ni0.1Al. We associate this result with the previously reported step-like change in the concentration dependence of lattice parameters in RE(Ni1-xCux)Al pseudo-ternary compounds. Our results corroborate the scenario for the RTX compounds with the ZrNiAl-type structure based on existence of a narrow interval of forbidden c/a values. For TbPdAl, TbNiAl and TbPd0.9Ni0.1Al we observed also a certain temperature interval of coexistence of two ZrNiAl-type phases characterized by two distinctly different c/a values. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.physb.2006.01.437

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

X-Ray powder diffraction method is used to investigate the effect of magnetic ordering and external magnetic field on crystal structure of Laves phase intermetallic compound ErCo2. The diffraction patterns were recorded at temperatures from 300 K down to 8.5 K in magnetic field up to 5 T. Distortion of the room-temperature cubic structure was found in magnetically ordered state below 32 K. The symmetry at low temperature is rhombohedral in agreement with literature results. Or lower symmetry than it. However the symmetry of the unit cell increases to cubic in external magnetic field of 5 T. (c) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.physb.2006.01.514

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記述言語：英語   出版者・発行元：JAPAN INST METALS  

DOI： 10.1113/jphysiol.2006.114231

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER/PLENUM PUBLISHERS  

The detailed topology of the Fermi surface of the quasi-one-dimensional conductor (DMET)(2)I-3 was investigated by the magnetooptical measurements. A pair of planar Fermi surface which has higher corrugations of Fourier components was observed. This result seems to suggest that the metallic state of this salt is stabilized by the higher corrugations of the Fermi surface.

DOI： 10.1007/s10909-006-9159-y

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

We have studied the magnetic properties of Ce(Fe1 xCox)(2) with x = 0 and 0.05 by magnetization measurements under high pressure. In both compound, the remarkable suppression of the magnetization is observed below T* in the ferromagnetic (FM) state under 1.2 GPa. T* shifts to lower temperature with increasing the magnetic field, and the extrapolated value to the zero magnetic field is estimated to be 95 and 123 K. These high pressure and magnetic field effects are probably due to the enhancement and the suppression of the AFM spin fluctuation, respectively. (c) 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jallcom.2005.04.057

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

A series of nanocomposite thin films, composed of α-Fe and c-axis oriented SmFe12 phases, has been synthesized by rf magnetron sputtering onto heated glass substrates. The volume fraction of α-Fe, VFe, in the obtained films ranges from 5% to 85%. According to the Rietveld analysis of X-ray diffraction patterns, the c-axis of each SmFe 12 grain was estimated to locate within a cone with its symmetry axis being normal to the film plane and with the cone angle of 7°. For samples with VFe &lt; 30%, the demagnetization curves with fields applied normal to the film plane have exhibited a good squareness. In small VFe films, the coercivity Hc increased with increasing VFe, took a maximum for VFe ∼ 25%, and then decreased. In the reference system of randomly aligned SmFe12/α-Fe films, on the other hand, we confirmed that Hc decreased monotonically with increasing VFe. © 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jallcom.2005.04.108

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1109/INTMAG.2006.374945

Scopus

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：AMER INST PHYSICS  

We have performed specific heat measurements of a high-quality polycrystalline sample of CuV2S4. Two anomalies associated with charge density wave (CDW) transitions are clearly observed at T-t1 = 92 K and T-t2h = 58 K. The anomalies at T-t1 and T-t2h show lambda-type and spike-shaped behavior, indicating second and first order phase transitions, respectively. The electronic specific heat coefficient gamma and the Debye temperature Theta(D) are estimated to be 36 mJ/moIK(2) and 347 K, respectively. gamma of CuV2S4 is much larger than that of CuTi2S4, whereas CuTi2S4 exhibits a CDW gap at low temperature. This enhancement of gamma is probably attributed not only to the electron-phonon interaction but also to electron-electron interactions.

DOI： 10.1063/1.2355192

Web of Science

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IOP PUBLISHING LTD  

Measurements of high-field magnetization up to 18 T, magnetic susceptibility and specific heat have been performed on a tetragonal NdRh2Ge2 single crystal and polycrystalline sample. From the temperature dependences of magnetic susceptibilities, this compound shows an antiferromagnetic behaviour with Neel temperature of 50 K. Another magnetic transition is observed at 37 K. At low temperatures, a multi-step metamagnetic behaviour is observed along the easy c-axis and a strong magnetic anisotropy is seen. The saturation magnetic moment is estimated to be 2.76 mu(B)/f.u.. There are five magnetic phases below the induced ferromagnetic phase in the H-T magnetic phase diagram. To discuss the magnetic behaviours, the CEF analysis has been made.

DOI： 10.1088/1/1742-6596/51/1/012

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IOP PUBLISHING LTD  

We have conducted low- and high-field magnetization measurements and neutron diffraction experiments on NdxEr1-xMn6Sn6 alloys (0 &lt;= x &lt;= 0.5) with hexagonal MgFe6Ge6 type structure. The alloy with x = 0.1 shows a complex helical antiferromagnetism with the magnetic moments rotating in the c plane below the Curie temperature T-C = 340 K, and a ferrimagnetism below the temperature T-t = 100 K. In the ferrimagnetic state, the magnetic moments mu(Mn) and mu(Nd) are parallel to each other, and antiparallel to mu(Er). The alloy with x = 0.4 shows also a similar ferrimagnetic structure below the Curie temperature T-C = 360 K. It is likely that the each magnetic moments are keep a constant values of mu(Mn) = 2.3 mu(B)/Mn atom, mu(Nd) = 3 mu(B)/Nd atom and mu(Er) = 9 mu(B)/Nd atom at 10 K in the whole composition (0 &lt; x &lt;= 0.5). The ferrimagnetic arrangements for the alloys with 0.2 &lt;= x &lt;= 0.5 are not almost disturbed by magnetic field up to 26 T at 4.2 K.

DOI： 10.1088/1/1742-6596/51/1/008

Web of Science

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Substitution of Y for U in the itinerant 5f-electron metamagnet, UCoAl, transforms the system to a ferromagnetic state. Application of external hydrostatic pressure above 0.3GPa suppresses the spontaneous ferromagnetism and restores the paramagnetism with field-induced transition to ferromagnetic state. However, the transition becomes of the second order instead of the first-order one in parent UCoAl. © 2006 Taylor &amp
Francis.

DOI： 10.1080/08957950601103973

Scopus

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

We have performed magnetooptical measurements of β′′-(BEDT-TTF)(TCNQ) using a cavity perturbation technique with a millimeter vector network analyzer (MVNA) and a 14 T superconducting magnet at IMR, Tohoku University. The results of ADMRO and SdH measurements at low temperatures are not consistent with the band calculation result. Therefore, we are interested in Fermi surfaces at low temperatures and have performed magnetooptical measurements of β′′-(BEDT-TTF)(TCNQ). Although the band calculation and ADMRO results suggest the existence of Q1D FS, our results suggest the existence of Q2D FS only. From the results of magnetooptical measurements, we discuss the FS topology of this system at low temperatures. © 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.synthmet.2005.07.308

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPAN INST METALS  

We performed the powder X-ray diffraction measurements in magnetic fields up to 5T for Gd-5(Ge1.95Fe0.05)Si-2 and Gd-5(Ge(1.8)Fc(0.2))Si-2-With heating from 8 K, the matrix of Gd-5(Ge1.95Fe0.05)Si-2 clearly shows a structural transition from an orthorhombic to a monoclinic structure at the Curie temperature (Tc = 276 K). On the other hand, the matrix of Gd-5(Ge1.8Fe0.2)Si-2 with the orthorhombic structure in the ferromagnetic state shows two-phases co-existence of the orthorhombic and the monoclinic structures above Tc = 303 K, indicating that a small amount of the matrix participates in the transformation. For both samples, the monoclinic structure is suppressed but the orthorhombic structure is enhanced just above Tc by applying a magnetic field, which closely relates to the magnetization process.

DOI： 10.2320/matertrans.46.2011

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPAN SOC APPLIED PHYSICS  

A rotational resonant cavity equipped with a millimeter vector network analyzer (MVNA) and a 14T solenoid type superconducting magnet has been developed. The available frequency range is about 50-100GHz. The temperature can decrease to 1.5 K. The cavity can rotate within the precision of one degree. As an example of the application of the new resonant cavity, we have performed detailed magnetooptical measurements of an organic conductor to estimate the Fermi surface topology. The Fermi surface of the quasi-one-dimensional conductor (DMET)(2)I(3) is discussed.

DOI： 10.1143/JJAP.44.4930

Web of Science

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

A series of Nd2Fe14B/α-Fe nanocomposite thin films, in which the crystallites of the Nd2Fe14B phase are well-oriented, has been synthesized by RF magnetron sputtering onto heated glass substrates. Magnetization curves exhibited single-phase-like hysteresis loops, suggesting that the two phases are firmly exchange-coupled. By comparing the observed magnetization curves with the micromagnetic calculations, we have estimated the intergrain exchange-coupling constants. © 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jmmm.2004.11.407

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPAN SOC APPLIED PHYSICS  

The high-field X-ray diffraction measurement of a re-entrant ferromagnet SmMn2Ge2 with a tetragonal structure was carried out. The unit cell volume contracts by approximately 0.3% in the antiferromagnetic (AFM) state, compared with that of the ferromagnetic (FM) state. In the AFM state, the structural distortion recovers due to a high magnetic field, accompanied by the metamagnetic transition from the AFM state to the forced FM state.

DOI： 10.1143/JJAP.44.1258

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PROGRESS THEORETICAL PHYSICS PUBLICATION OFFICE  

The EPR spectra along different crystallographic axes for single crystals of CuGeO3 containing 1% of Fe impurity have been studied in the frequency range 60-360 GHz at temperatures 0.5-30 K. The analysis based on the Oshikawa-Affleck theory suggests that the temperature dependences of the line width and g-factor are formed as a result of the competition between interchain antiferromagnetic interactions and staggered Zeeman energy. It is found that staggered magnetic moments in CuGeO3:Fe are located predominantly along b axis.

DOI： 10.1143/PTPS.159.387

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PHYSICAL SOC JAPAN  

Submillimeter and millimeter wave electron spin resonance (ESR) measurements of BaCu2(Si1-xGex)(2)O-7, which is a mixed system of an S=1/2 one-dimensional Heisenberg antiferromagnet with the Dzyaloshinskii-Moriya interaction, have been performed to investigate the limitations of the Oshikawa-Affleck theory for the ESR of an S=1/2 one-dimensional Heisenberg antiferromagnet with a staggered field. The magnetic field dependence of the linewidth and the field induced energy gap will be discussed in connection with the Oshikawa-Affleck theory.

DOI： 10.1143/JPSJ.74.80

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMERICAN PHYSICAL SOC  

The transition between the antiferromagnetic (AF) and the ferromagnetic (F) states has been investigated with regard to the magnetovolume effect and the spin-fluctuation characteristics in La(FexAl1-x)(13) compounds. The volume V and amplitude of the local magnetic moment M-loc are different between the AF and F states. In the AF state, the field-induced first-order AF-F transition appears and the transition proceeds with two steps in higher Fe concentration regions. The complex temperature dependence of the AF-F transition field is explained by the contribution from both the magnetic and elastic energies caused by the significant temperature variation of amplitude of M-loc. For the two-step transitions, the spin-floplike transition and the increase in amplitude of M-loc occur at the first- and second-step transitions, respectively. In other words, both the localized moment and the itinerant-electron characteristics are concurrently observed.

DOI： 10.1103/PhysRevB.70.214405

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

We have developed a new magneto-optical measurement system with a rotational cavity. It consists of a millimeter vector network analyzer and a 15T solenoid type superconducting magnet and it can go down to 1.5 K. The rotational cavity can be used in the transmission configuration and the rotation can be performed up to almost 360 degrees in 1 degree precision. We will show the magneto-optical measurement results of, beta ''-(BEDT-TTF)(TCNQ) using our new system. We observe the quasi-two-dimensional periodic orbit resonance (POR) in beta ''-(BEDT-TTF)(TCNQ). The Fermi surfaces of this system will be discussed.

DOI： 10.1142/S0217979204027487

Web of Science

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PHYSICAL SOC JAPAN  

We have studied the magnetic properties of Ce(Fe1-xCox)(2) with x less than or equal to 0.1 by magnetization measurements under high pressures up to 1.2 GPa. In pure CeFe2, the Curie temperature T-C decreases, and the saturation magnetization M-s is suppressed by applying pressure. In Co substitution compounds, the transition temperature T-A from the ferromagnetic (FM) to the antiferromagnetic (AFM) states and the metamagnetic transition field B-c increase with increasing pressure, while T-C and the magnetization of the spontaneous and field-induced FM states decrease. The obtained results indicate that the AFM state becomes stable by the lattice contraction.

DOI： 10.1143/JPSJ.73.1982

Web of Science

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC  

We are now developing a 30 T hybrid magnet utilizing a cryocooler-cooled superconducting magnet wound with highly strengthened (Nb, Ti)(3)Sn. Diameter of the room temperature bore of the superconducting magnet is 360 mm and it generates 11.1 T. Water cooled resistive insert magnet generates 18.9 T, thus the hybrid magnet generates a central field of 30.0 T. The (Nb, Ti)(3)Sn multifilamentary wires are strengthened by Cu/NbTi composite which volume ratio in conductor is about 35%. The reinforcing Cu/NbTi composite changes to CuTi intermetallic compounds during heat treatment for reaction of (Nb, Ti)(3)Sn phase formation. The Nb3Sn coil with inner diameter of 400 mm will be fabricated by wind and react method with Cu/NbTi reinforced (Nb, Ti)(3)Sn wires. The innermost section of Nb3Sn coil is wound with a wire which diameter is 1.85 mm and next second section is wound with a wire diameter of 1.8 mm. The Nb3Sn coil is operated at 303 A and generates 5.8 T. The NbTi coil is wound with NbTi wires of 2.0 mm and 1.6 mm diameters. The NbTi coil generates 5.3 T at an operating current of 350 A. The maximum hoop stress is under 220 MPa for Nb3Sn coil and 200 MPa for NbTi coil.

DOI： 10.1109/TASC.2004.829672

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER INST PHYSICS  

Magnetovolume effect due to the itinerant-electron metamagnetic (IEM) transition in La(Fe0.88Si0.12)(13) has been investigated by x-ray diffraction measurements in high magnetic fields. No crystal structure change was confirmed after the IEM transition. The relative change in the lattice constant measured perpendicular to the magnetic field direction is similar to the longitudinal linear magnetostriction, and hence the volume change due to the IEM transition is isotropic. The volume change in both the ferromagnetic and the paramagnetic states is proportional to the square of the magnetization, though the magnetovolume coupling constant in the former is smaller than that in the latter. (C) 2004 American Institute of Physics.

DOI： 10.1063/1.1667455

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

We have performed the high-field ESR of the one-dimensional BaCu2(Si1-xGex)(2)O-7 (x = 0.65) antiferromagnet at 0.5 and 1.8 Kin the wider frequency and magnetic field region (40-500 GHz, up to 30 T), and found the breather excitation predicted by the Oshikawa-Affleck (OA) theory. The observed field-induced gap for Bparallel toc (chain direction) shows the B-2/3 dependence suggested by the OA theory, and the dependence is weak for the other directions which is consistent with the anisotropy of the Dzyaloshinsky-Moriya interaction. The results will be also discussed in connection with the breather excitation observed in Cu-benzoate. (C) 2003 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jmmm.2003.12.547

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

The temperature and magnetic field dependences of lattice parameter for Ce(Fe1-xCox)(2) with x = 0, 0.05 and 0.10 are examined by powder X-ray diffraction measurement. The strong correlation between structural phase and magnetic state in these compounds is discussed. (C) 2003 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jmmm.2003.11.245

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

We have performed the magnetization and X-ray diffraction measurements on Mn3Ga1-xAlxC (0 &lt;= x &lt;= 0.1) with a perovskite-type structure in the temperature T range from 5 to 400 K to investigate the behavior of the complicated magnetic phase transitions. The obtained results suggest that the crystallographic character is closely correlated to the magnetic properties. The new magnetic phase diagram of this system is presented, which indicates the two-phases coexistence in Mn3Ga1-xAlxC at lower temperature. (C) 2003 Elsevier B. V. All rights reserved.

DOI： 10.1016/j.jmmm.2003.11.312

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD  

(n-C3H7)(4)N[(FeFeIII)-Fe-II(dto)(3)] shows a new type of first order phase transition called chare-transfer phase transition around 120 K. where the charge transfer between Fe-II and Fe-III occurs reversibly. Recently, we have succeeded in obtaining single crystals of the title complex and determined the crystal Structure at room temperature. Crystal data: space group P6(3), a = 10.0618(5) Angstrom. c = 16.0424(7) Angstrom. V = 1406.54(12)Angstrom, Z = 2. Moreover. we have investigated the structural transition caused by the charge-transfer phase transition by means of powder X-ray diffraction measurement. When the temperature is decreased. the a-axis. which corresponds to the hexagonal ring size in two-dimensional honeycomb network structure of [Fe-II Fe-III(dto)(3)](infinity). contracts by 0.1 Angstrom at the charge-transfer transition temperature (T-CT) while the c-axis. perpendicular to the honeycomb network layer. elongates by 0.1 Angstrom at T-CT. Consequently, when the temperature is decreased, the unit cell volume decreases without noticeable anomaly around T-CT, which is responsible for the quite sniall vibrational contribution to the entropy change. compared with usual spin crossover transition. Thus, the charge-transfer phase transition around 120 K for (n-C3H7)(4)N[Fe-II Fe-III(dto)(3)] is regarded as spin entropy driven phase transition. (C) 2004 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ssc.2004.02.034

Web of Science

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

The magnetic and structural properties of Ce(Fe0.9Co0.1)(2) with the C15 cubic Laves-phase structure have been studied by magnetization measurement in high magnetic fields under high pressures, and powder X-ray diffraction measurement in fields up to 5 T. The C15 cubic structure is distorted to rhombohedral symmetry accompanied with the magnetic phase transition from the ferromagnetic to the antiferromagnetic state, which recovered the C15 structure by applying the magnetic field. The antiferromagnetic phase is induced by the lattice contraction due to hydrostatic pressure. Obtained results suggest that the AFM correlation due to the Cc 4f-Fe 3d hybridization plays an important role on the structural and magnetic properties. (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.physb.2004.01.047

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Magneto-optical measurements of a quasi-one-dimensional (q1D) organic superconductor (DMET)(2)I-3 has been performed by using a cavity perturbation technique. Several resonant absorption lines, which can be attributed to the q1D periodic orbit resonance (q1D POR), as well as the quite unusual high-order q1D POR coming from the corrugated Fermi surface (FS) in the interlayer direction were observed. Moreover, other harmonic resonances are also observed when the AC electric field is applied along the c*-axis. We will also show its estimated q1D FS from the data analysis where the estimated FS clearly shows why there is no spin-density-wave or charge-density-wave transition in (DMET)(2)I-3 despite having a q1D FS. (C) 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.physb.2004.01.112

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Magnetooptical measurements have been performed on β″-(BEDT-TTF) (TCNQ) using the cavity perturbation techniques. β″-(BEDT-TTF)(TCNQ) has very exotic Fermi surface (FS). Several harmonic resonances were observed at various angles. We consider these resonances as q1D-periodic orbit resonance. The obtained Fermi velocity and the scattering time are 4.4×10 4m/s and 2.1×10-11s, respectively. When the magnetic field was rotated in the b*a-plane, the similar resonances are observed. According to these results, the FS topology of the system at low temperature is discussed. © 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.physb.2004.01.111

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PHYSICAL SOC JAPAN  

We have studied the magnetic and structural properties of Ce(Fe0.9Co0.1)(2) with the C15 cubic Laves-phase structure by low-temperature x-ray diffraction measurements in magnetic fields up to 5 T, and in the temperature range from 9 to 300 K. The C15 structure is distorted to rhombohedral symmetry at 90 K in zero magnetic field, accompanied with the magnetic phase transition from the ferromagnetic (FM) to the antiferromagnetic (AFM) states with decreasing temperature. In the AFM state, it is observed clearly that the rhombohedral distortion state recovers the C15 structure by applying magnetic field, accompanied with the metamagnetic transition from the AFM to the forced FM states with a hysteresis in the magnetization process.

DOI： 10.1143/JPSJ.73.676

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：IEEE  

We have developed a rotational resonant cavity equipped with the millimetre vector network analyser and the 14 T superconducting solenoid magnet. The measurement can be performed down to 1.6 K and the frequency range is about 50100 GHz. As an example of its application, the results of the precise angular dependence measurements of the quasi one dimensional organic conductor (DMET)(2)I-3 are presented.

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：IOP PUBLISHING LTD  

Cyclotron resonance (CR) measurements on high-quality single crystals of rare-earth monopnictides have been performed in the frequency range from 50 to 190 GHz. We have successfully observed CR signals for a strongly correlated electron system, CeSb, as well as other rare-earth monopnictides, LaSb and PrSb. We have also observed Doppler-shifted CR including nonlinear behaviour in the frequency-field diagrams.

DOI： 10.1088/0953-8984/15/28/333

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PHYSICAL SOC JAPAN  

Electron spin resonance (ESR) measurements on single crystals of GdX (X = P, As, Sb and Bi) have been performed in the temperature range from 50 to 1.7 K and in the frequency range from 50 to 109 GHz to obtain microscopic information on the magnetic properties. The results obtained indicate that GdX is an "easy-plane" antiferromagnet with the magnetic moment lying in the (111) plane below the Neel temperature. In addition, ESR affected by hyperfine interaction was observed in GdBi.

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

An electron spin resonance (ESR) measurement system for use at ultralow temperatures using a He-3-He-4 dilution refrigerator has been developed down to 160 mK. As the first experiment, the ESR was measured on a quantum spin chain Cu benzoate, in which a field-induced gap was recently found. The evaluation of a new ESR mode, so-called breather mode, was found at the lowest temperatures. In the present work, we observed a smaller gap in Hparallel tob by suppressing of the thermal excitation. (C) 2003 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0921-4526(02)02433-X

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

An antiferromagnetic resonance in λ-(BETS)2FeCl 4 has been observed at 23-110 GHz in the antiferromagnetic insulating state. The frequency-field diagram, which is basically explained by a two-sublattice model, indicates that the spin system has a biaxial anisotropy and the a*-axis is close to the hard axis. © 2003 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0379-6779(02)00745-2

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

Magnetooptical measurements of quasi-one-dimensional organic conductor (DMET)(2)I-3 have been performed by using a cavity perturbation technique with Millimeter Vector Network Analyzer (MVNA). Several resonances are observed and these resonances disappear when the magnetic field is applied nearby the conducting b-axis. These resonances seem to come from the periodic modulation of group velocities of the carriers on the quasi-one-dimensional Fermi surface (q1D FS). However, these resonances show a different angular dependence with the Fermi traversal resonance (FTR) or quasi-one-dimensional periodic orbit resonance (q1D POR).

DOI： 10.1016/S0379-6779(02)00721-X

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Magneto-optical measurements of β-(BEDT-TTF)2AuI 2, which has an Isotropic two dimensional Fermi surface in the ab-plane, have been performed at 1.8 K by using cavity perturbation technique with steady magnetic field and mosaic transmission technique with pulsed magnetic field. A cyclotron resonance coming from the quasi two dimensional Fermi surface has been observed in both measurements for H⊥ab-plane. Obtained effective mass was 0.9 mc and this result is smaller than the mass obtained by the Shubnikov-de Haas measurement, which suggests the existence of electron-electron interactions in the system. © 2003 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0379-6779(02)00718-X

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PHYSICAL SOC JAPAN  

DOI： 10.1143/JPSJ.72.767

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMERICAN PHYSICAL SOC  

From microwave cavity transmission measurements at 23-110 GHz on lambda-(BEDT-TSF)(2)FeCl4, we have observed an antiferromagnetic resonance (AFMR) in the antiferromagnetic insulating state below the metal-to-insulator transition temperature of T-MI=8.3 K. The frequency-field dependence is fundamentally reproduced with a two-sublattice model for a biaxial anisotropy. The easy axis is confirmed to be the direction tilted by 30degrees from c to b(*), and the hard axis is found to be close to a(*). The spin-flop field is identified to be 1.3 T through the frequency-field dependence for the easy axis. The AFMR is interpreted to be caused by spin waves excited on the pi spins, exclusively due to the large pi-pi exchange interaction estimated by theoretical calculations. The exchange field and anisotropy fields for pi spin systems at 1.2 K are evaluated to be H(E)similar to330 T, H(A)(1)similar to1.5x10(-3) T for the intermediate axis and H(A)(2)similar to5.0x10(-3) T for the hard axis, respectively.

DOI： 10.1103/PhysRevB.67.020408

Web of Science

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

From microwave cavity transmission measurements at 23–110 GHz on (formula presented) we have observed an antiferromagnetic resonance (AFMR) in the antiferromagnetic insulating state below the metal-to-insulator transition temperature of (formula presented) The frequency-field dependence is fundamentally reproduced with a two-sublattice model for a biaxial anisotropy. The easy axis is confirmed to be the direction tilted by (formula presented) from c to (formula presented) and the hard axis is found to be close to (formula presented) The spin-flop field is identified to be 1.3 T through the frequency-field dependence for the easy axis. The AFMR is interpreted to be caused by spin waves excited on the (formula presented) spins, exclusively due to the large (formula presented) exchange interaction estimated by theoretical calculations. The exchange field and anisotropy fields for (formula presented) spin systems at 1.2 K are evaluated to be (formula presented) (formula presented) for the intermediate axis and (formula presented) T for the hard axis, respectively. © 2003 The American Physical Society.

DOI： 10.1103/PhysRevB.67.020408

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Physical Society of Japan  

Electron spin resonance (ESR) measurements on single crystals of GdX (X = P, As, Sb and Bi) have been performed in the temperature range from 50 to 1.7 K and in the frequency range from 50 to 109 GHz to obtain microscopic information on the magnetic properties. The results obtained indicate that GdX is an "easy-plane" antiferromagnet with the magnetic moment lying in the (111) plane below the Néel temperature. In addition, ESR affected by hyperfine interaction was observed in GdBi. © 2003 The Physical Society Japan.

DOI： 10.1143/JPSJS.72SB.145

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

For clarifying the role that the interstitial N atoms played on the microscopic scale for basic magnetism in R2Fe17N3, we determined the enhancements of Fe magnetic moments on the crystallographically different atomic sites and crystalline electric field parameter A, upon nitrogenation by neutron diffraction studies of the rhombohedral Y2Fe17 and Y2Fe17N3.1 and high-field magnetization measurements of single crystalline Nd2Fe17 and Nd2Fe17N3, respectively. The results obtained are compared with those estimated by the band structure calculation. For clarifying the coercivity mechanism in Sm2Fe17N3, we also examined the particle (powder) size and surface cleaning effects on the coercive field mu(0)H(e) for the Sm2Fe17N3 single crystal powder. The results indicate that mu(0)H(e) monotonically decreases with increasing the particle size, suggesting that the coercivity mechanism is of a nucleation type. When there are many nucleation sites on the surface of Sm2FeN3 powder before surface cleaning, the value of mu(0)H(e) is relatively small and reveals strong temperature dependence, while mu(0)H(e) is strongly enhanced by surface cleaning, leading to relatively weak temperature dependence. (C) 2002 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0304-8853(01)01189-1

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER INST PHYSICS  

An electron spin resonance (ESR) apparatus with a high sensitivity vector network analyzer has been developed for use at ultralow temperatures. The microwave frequency can be varied between 45 and 110 GHz. The resonant cavity was installed in a He-3-He-4 dilution refrigerator which provides ultralow temperatures down to 160 mK. In order to avoid the heating of the cavity and the sample by microwaves or heat leaks in the cryostat, attenuators and thermal anchors were placed at the most suitable positions. As the first experiment, the ESR was measured for a quantum spin chain Cu benzoate. The breather mode, which is a new ESR mode caused by a field induced gap, has been clearly observed at the lowest temperatures. (C) 2002 American Institute of Physics.

DOI： 10.1063/1.1448901

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：Institute of Electrical and Electronics Engineers Inc.  

The cyclotron resonance is the best way to determine the effective masses of conductors and it is interesting to compare them with other effective masses determined by the de Haas oscillations. According to Kohn's theorem, they are not necessarily coincident with each other because an electron-electron correlation in the strongly correlated electron systems contributes to only the case of the de Haas oscillations. This argument has been studied in the case of organic conductors. On the other hand, it has been difficult to observe the cyclotron resonance absorption in rare-earth semimetals due to necessity of high frequency equipment, high magnetic field, very low temperature and high quality specimen. We have succeeded in observing cyclotron resonance in some rare-earth monopnictide compounds RX (R=rare earth atom, X=pnictgen atom) with NaCl type crystal structure and discussed the relationship between two kinds of masses of these materials. As reference materials, nonmagnetic LaSb and PrSb were also studied. In these cases, we have found new nonlinear resonance lines in addition to the normal cyclotron resonance whose resonance frequencies are linear with respect to magnetic field intensity. We ascribe this effect to the Doppler shift caused by coupling of cyclotron motion of carriers with the Alfven wave propagating in the material.

DOI： 10.1109/ICIMW.2002.1076051

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The cyclotron effective masses of rare earth monopnictides were determined. These masses were obtained by cyclotron resonance (CR) measurements in the frequency range between 56 GHz and 190 GHz in the temperature range between 50 K and 0.5 K. The experimental results on CR measurements for single crystals of rare earth compounds were presented using a vector network analyzer (AB millimeter) and a resonant cavity. In addition to normal cyclotron resonance, two anomalous absorption lines were observed for the high quality single crystal of LaSb.

DOI： 10.1016/S0022-3697(02)00053-7

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PHYSICAL SOC JAPAN  

An electron spin resonance (ESR) measurement system for use at ultralow temperatures using a He-3-He-4 dilution refrigerator has been developed. As the first experiment. the ESR was measured on a quantum spin chain Cu benzoate clown to 160 ml. in which a field-induced gap was recently found.((4)) The evaluation of a new ESR mode. the so-called breather mode, was found at the lowest temperatures. In the previous ESR down to 0.5 K, this mode was clearly found for H // c. in which the magnitude of the gap is largest. In the present work. the achievement of low temperatures enabled us to observe a smaller gap in H // b by suppressing the thermal excitation. The magnitude of the field-induced gap evaluated from the nonlinear field dependence of the mode shows good agreement with that determined by previous specific heat measurements.

DOI： 10.1143/JPSJ.70.2259

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Thin-film magnets, composed of nanophase dispersed Nd2Fe14B and α-Fe have been synthesized by rf magnetron sputtering. With increasing α-Fe volume fraction VFe, the saturation magnetization increased linearly, while the coercivity decreased. Ferromagnetic resonance measurements were made by using a high-frequency and high-field ESR apparatus, which exhibited two absorption peaks. A model calculation of the resonance field was made for a simplified hard/soft two-sublattice system to analyze these results. Estimated values of the exchange-coupling constant are in good agreement with those deduced from micro-magnetic analysis of the magnetization curves.

DOI： 10.1109/20.951237

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Cyclotron resonances of quasi-two-dimensional organic conductor θ-(BEDT-TTF)2I3 have been observed by using Millimeter Vector Network Analyzer (MVNA), V- and W-Band Cavity at 0.5K. Two resonances are observed, and the mode coupling in the cavity suggests that the resonances are cyclotron resonances. Obtained effective masses 1.03me and 2.14me are assigned to be α and β orbits, respectively.

DOI： 10.1016/S0379-6779(00)00711-6

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Magnetization measurements have been performed on single-phase Ce2Fe17 with a rhombohedral structure under high pressures up to 1.2 GPa and in magnetic fields B up to 17T to clarify the pressure effect on the magnetic phase transitions. At 0.8 GPa, we observed at least seven magnetic phases in the B-T plane. The results obtained indicate that the hybridization between the Fe 3d- and Ce 4f-electron states plays an important role for the magnetic properties of Ce2Fe17. (C) 2001 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0921-4526(00)00634-7

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

In this paper, we present our recent results of studies of the nitrogen absorption process, magnetization measurements, and neutron powder-diffraction measurements for interstitially modified nitrides (Formula presented) Ce, Nd, and Sm) and (Formula presented) (1) The studies of nitrogen absorption rates in the (Formula presented) under various (Formula presented)-gas pressure up to 6 MPa indicated that the nitrogen absorption into grain interior is promoted by diffusion of nitrogen atoms under low (Formula presented)-gas pressure, while under high (Formula presented)-gas pressure, the nitrogen absorption is promoted by the grain growth of fully nitrogenated phase (Formula presented) rather than the diffusion, making high-pressure nitrogenation effective for synthesizing high-quality nitrides. (2) The high-field magnetization measurements of the (Formula presented) and (Formula presented) single crystals at 4.2 K indicated that interstitial modification of nitrogen atoms gives rise to a strong enhancement of crystalline electric field (CEF) acting on R atoms, leading to almost three times larger CEF-parameter (Formula presented) upon nitrogenation. (3) Neutron powder-diffraction studies of (Formula presented) and (Formula presented) with rhombohedral structure indicated that the N atoms fully occupy at the (Formula presented) site. The introduction of N atoms into (Formula presented) brought such a strong modification in the Fe magnetic moment that the moment of the (Formula presented) atoms being the nearest to the (Formula presented) atoms is the smallest, whereas the (Formula presented) and/or (Formula presented) atoms being relatively farther from the (Formula presented) atoms have the largest moments at 10 K. The results obtained are discussed on the basis of the calculated electronic band structures. © 2000 The American Physical Society.

DOI： 10.1103/PhysRevB.61.9475

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人応用物理学会  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）