検索対象:     
報告書番号:
※ 半角英数字
 年 ~ 
 年
検索結果: 12 件中 1件目~12件目を表示
  • 1

発表形式

Initialising ...

選択項目を絞り込む

掲載資料名

Initialising ...

発表会議名

Initialising ...

筆頭著者名

Initialising ...

キーワード

Initialising ...

発表言語

Initialising ...

発行年

Initialising ...

開催年

Initialising ...

選択した検索結果をダウンロード

論文

Massive Dirac magnons in the three-dimensional honeycomb magnetic oxide FeTiO$$_3$$

Chung, J.-H.*; Kwangwoo, S.*; Yokoo, Tetsuya R.; 植田 大地*; 今井 正樹; Kim, H.-S.; Kiem, D. H.; Han, M. J.*; 社本 真一

Scientific Reports (Internet), 15, p.5978_1 - 5978_10, 2025/02

 被引用回数:0 パーセンタイル:0.00(Multidisciplinary Sciences)

Two dimensional honeycomb ferromagnets host massless Dirac magnons which are a bosonic analogue of Dirac fermions in graphene. The Dirac magnons may become massive and topological when the time-reversal symmetry breaks and an energy gap opens up at the Dirac point, which was experimentally observed in Cr$$^{3+}$$-based van der Waals magnets. Here, we investigate the spin wave excitations in the $$3d$$ magnetic oxide FeTiO$$_3$$ with Fe$$^{2+}$$ electrons ($$3d^4$$). Using inelastic neutron scattering, we observe two magnon bands separated by a 1.2-meV gap at the Dirac points indicating that its Dirac magnons are massive. Using the linear spin-wave and density functional theory calculations, we find that the spin-orbit-coupled antisymmetric Dzyaloshinskii-Moriya exchanges can best account for the observed Dirac gap opening. The associated Berry curvature and Chern number ($$C^pm = pm 1$$) indicate that FeTiO$$_3$$ hosts topological spin excitations via time-reversal symmetry breaking of Dirac magnons.

論文

Magnetic layer thickness influence on magnetoelastic properties anisotropy in Co$$_{2}$$Fe$$_{0.4}$$Mn$$_{0.6}$$Si heusler alloy thin films

Nabialek, A.*; Chumak, O.*; 関 剛斎*; 高梨 弘毅; Baczewski, L. T.*; Szymczak, H.*

IEEE Transactions on Magnetics, 59(11), p.2501405_1 - 2501405_5, 2023/11

 被引用回数:2 パーセンタイル:30.27(Engineering, Electrical & Electronic)

The anisotropic magnetoelastic (ME) properties of epitaxial Co$$_{2}$$Fe$$_{0.4}$$Mn$$_{0.6}$$Si(CFMS) Heusler alloy thin films with thicknesses ranging from 8 to 100 nm were investigated using the strain-modulated ferromagnetic resonance (SMFMR) technique. The calculation of the first cubic magnetocrystalline (MC) constant ${it K}$ $$_{1}$$ and the two cubic ME constants ${it b}$ $$_{1}$$ and ${it b}$ $$_{2}$$ was carried out assuming the cubic symmetry of the magnetic layer. A significant negative perpendicular MC anisotropy, of the order of 10$$^{5}$$ J/m$$^{3}$$, was also observed. The investigated parameters were found to be dependent on the thickness of the magnetic layer. The thinnest magnetic layers showed the strongest cubic MC anisotropy and the weakest anisotropy of ME properties. These findings highlight the importance of considering the magnetic layer thickness when evaluating the anisotropy in the ME properties of Heusler alloy thin films.

論文

Magnetic properties of single crystalline Tb$$_5$$Sb$$_3$$

北折 暁*; 金澤 直也*; 木田 孝則*; 鳴海 康雄*; 萩原 政幸*; 金道 浩一*; 竹内 徹也*; 仲村 愛*; 青木 大*; 芳賀 芳範; et al.

Journal of the Physical Society of Japan, 92(2), p.024702_1 - 024702_6, 2023/02

 被引用回数:1 パーセンタイル:23.32(Physics, Multidisciplinary)

Magnetic properties of Tb$$_5$$Sb$$_3$$ are reported. Unlike previous investigations on a polycrystal showing multiple phase transitions, the present single crystal sample shows a single transition 133 K. It is also shown that the magnetic hysteresis increases at low temperatures.

論文

Single crystal growth and magnetic properties of $$alpha$$-Mn and $$beta$$-Mn

大貫 惇睦*; 青木 大*; 仲村 愛*; 松田 達磨*; 中島 美帆*; 芳賀 芳範; 竹内 徹也*

Journal of the Physical Society of Japan, 91(6), p.065001_1 - 065001_2, 2022/06

 被引用回数:0 パーセンタイル:0.00(Physics, Multidisciplinary)

Single crystals of $$alpha$$-Mn and $$beta$$-Mn are successfully grown. Non-Fermi-liquid relations of the low-temperature resistivity and specific heat are found in the spin-liquid state of $$beta$$-Mn. On the other hand, $$alpha$$-Mn exhibits antiferromagnetic transition.

論文

Spin glass behavior in EuCu$$_2$$Si$$_2$$ single crystal grown by the flux method

竹内 徹也*; 芳賀 芳範; 谷口 年史*; 伊覇 航*; 安次富 洋介*; 屋良 朝之*; 木田 孝則*; 田原 大夢*; 萩原 政幸*; 中島 美帆*; et al.

Journal of the Physical Society of Japan, 89(3), p.034705_1 - 034705_15, 2020/03

 被引用回数:0 パーセンタイル:0.00(Physics, Multidisciplinary)

Single crystals of EuCu$$_2$$Si$$_2$$ have been grown by the flux method and Bridgman method. The Eu ions of the Bridgman-grown crystal are nearly trivalent and fluctuate depending on the temperature. On the other hand, the Eu ions of flux-grown sample are divalent and thermally stable and show spin-glass behavior at low temperatures. Crystallographic analyses identified random replacement of Cu sites by Si only for the flux-grown samples. Such structural randomness leads to spin-glass features.

論文

Crystallographic, magnetic, thermal, and electric transport properties in UPtIn single crystal

松本 裕司*; 芳賀 芳範; 立岩 尚之; 山本 悦嗣; Fisk, Z.*

Journal of the Physical Society of Japan, 87(2), p.024706_1 - 024706_4, 2018/02

 被引用回数:0 パーセンタイル:0.00(Physics, Multidisciplinary)

Single crystal samples of UPtIn with the hexagonal structure are grown from indium flux. Strong uniaxial magnetic anisotropy is revealed from magnetic property measurements. Specific heat measurement reveals a significant deviation from $$T$$-linear behavior, indicating the smaller electronic specific heat than the previous study.

論文

Switching of magnetic ground states across the UIr$$_{1-x}$$Rh$$_x$$Ge alloy system

Pospisil, J.; 芳賀 芳範; 神戸 振作; 徳永 陽; 立岩 尚之; 青木 大*; 本多 史憲*; 仲村 愛*; 本間 佳哉*; 山本 悦嗣; et al.

Physical Review B, 95(15), p.155138_1 - 155138_15, 2017/04

 被引用回数:15 パーセンタイル:54.36(Materials Science, Multidisciplinary)

We investigated the evolution of magnetism in UIr$$_{1-x}$$Rh$$_x$$Ge system by systematic study on high-quality single crystals. We find a field-induced first order transition in the vicinity of the critical magnetic field along the $$b$$ axis in the entire UIr$$_{1-x}$$Rh$$_x$$Ge system, including the ferromagnetic region.

論文

Gamma radiation resistance of spin Seebeck devices

Yagmur, A.*; 内田 健一*; 井原 和紀*; 井岡 郁夫; 吉川 貴史*; 小野 円佳*; 遠藤 純一*; 柏木 王明*; 中島 哲也*; 桐原 明宏*; et al.

Applied Physics Letters, 109(24), p.243902_1 - 243902_4, 2016/12

 被引用回数:3 パーセンタイル:13.48(Physics, Applied)

スピンゼーベック効果(SSE)に基づく熱電素子の$$gamma$$線抵抗性を調べるため、約3$$times$$10$$^{5}$$Gyの$$gamma$$線照射試験を実施した。SSE素子には、Pt/Ni$$_{0.2}$$Zn$$_{0.3}$$Fe$$_{2.5}$$O$$_{4}$$/GlassとPt/Bi$$_{0.1}$$Y$$_{2.9}$$Fe$$_{5}$$O$$_{12}$$/Gd$$_{3}$$Ga$$_{5}$$O$$_{12}$$を用いた。SSE素子の熱電特性,磁気特性、構造は、$$gamma$$線照射により影響されないことを確認した。この結果は、SSE素子が厳しい照射環境でさえ熱電素子として適用可能なことを示した。

論文

Magnetic properties and structures of uranium-3d transition element alloys

濱口 由和; 好村 滋洋; 国富 信彦

Journal of the Physical Society of Japan, 17(SUPPL.B-3), p.46 - 48, 1962/00

抄録なし

口頭

Characterization of high-quality single crystal of unconventional superconductor UTe$$_2$$ and its magnetic responses

芳賀 芳範

no journal, , 

UTe$$_2$$ is known as an extremely unconventional superconductor. It is also clarified that physical properties both in normal and superconducting states are sample-dependent. Single crystal X-ray diffraction study was performed on UTe$$_2$$ with different quality revealing apparent uranium defects. The resulting difference of physical properties are discussed.

口頭

Crystal structure and magnetic properties of uranium-based intermetallic compound U$$_2$$Pt$$_6$$Al$$_{15}$$

芳賀 芳範; 山本 悦嗣; 松本 裕司*; 白崎 謙次*

no journal, , 

U$$_2$$Pt$$_6$$Al$$_{15}$$ is known as a uranium intermetallic compound with the hexagonal structure. Detailed crystal structure investigations revealed that uranium atoms form a honeycomb layer stacking along the c-axis. Two magnetic phase transitions were identified by thermodynamic measurements, suggesting a successive change in the magnetic structure.

口頭

Magnetic and transport characteristics of $$An$$TX$$_5$$ compounds

芳賀 芳範

no journal, , 

Actinides and rare-earths compounds $$An$$TX$$_5$$ ($$T$$ = transition metals, $$X$$ = Ga, In) with the tetragonal HoCoGa$$_5$$-type structure (so-called 115 compounds) are one of the most extensively studied systems in correlated electron system because of the emergence of intriguing physical properties including heavy fermion superconductivity and various magnetic orderings. In these compounds, 5f electrons are responsible for both magnetic and transport characteristics. In particular, we discuss the emergence of a magnetic ordering in iso-electronic compounds URhGa$$_5$$ and URhIn$$_5$$.

12 件中 1件目~12件目を表示
  • 1