TOHOKU UNIVERSITY
Seki Lab (Magnetic Materials), IMR
Publications
Papers
2024
“Enhanced orbital magnetic moment in an FeCo-BaF2 granular film revealed by x-ray magnetic circular dichroism”
Keita Ito, Nobukiyo Kobayashi, Kenji Ikeda, Takumi Ichimura, Mitsuhiro Matsuki, Takahide Kubota, Kenta Amemiya, Akio Kimura, Koki Takanashi
J. Magn. Magn. Mater., Vol.606, (2024) pp. 172361-1-5
“Magnetoelastic coupling for Fe–Ga thin films epitaxially grown on different substrates”
Hao Ding, Keita Ito, Yasushi Endo, Koki Takanashi, and Takeshi Seki
J. Phys. D: Appl. Phys., Vol.57, (2024) pp. 385002-1-10
“High-Throughput Optimization of Magnetoresistance Materials Based on Lock-In Thermography”
Rajkumar Modak, Takamasa Hirai, Yuya Sakuraba, Seiji Mitani, Koichi Oyanagi, Takumi Yamazaki, Takeshi Seki, and Ken-ichi Uchida
Adv. Physics Res., Vol.3, (2024) pp. 2400021-1-8
“Spin caloritronics in metallic superlattices (Topical Review)”
Takeshi Seki, Ken-ichi Uchida, and Koki Takanashi
J. Phys.: Condens. Matter, Vol.36, (2024) pp. 333001-1-11
“Negative anomalous Nernst coefficient in a MnAlGe film and its enhancement in a (Mn-Cr)AlGe film”
Keita Ito, Takahide Kubota, and Koki Takanashi
Phys. Rev. Applied, Vol.21, (2024) pp. 054012-1-7
“Zero-magnetic-field operation of ordinary-Nernst-effect-based transverse thermoelectric module using embedded permanent magnets”
Masayuki Murata, Takamasa Hirai, Takeshi Seki, and Ken-ichi Uchida
Appl. Phys. Lett., Vol.124, (2024) pp. 193901-1-7
[Featured Article]
“Non-coplanar spin structure in a metallic thin film of triangular lattice antiferromagnet CrSe”
Yusuke Tajima, Junichi Shiogai, Kohei Ueda, Hirotake Suzaki, Kensuke Takaki, Takeshi Seki, Kazutaka Kudo, and Jobu Matsuno
APL Mater., Vol.12, (2024) pp. 041112-1-8
“Room temperature chirality switching and detection in a helimagnetic MnAu2 thin film”
Hidetoshi Masuda, Takeshi Seki, Jun-ichiro Ohe, Yoichi Nii, Hiroto Masuda, Koki Takanashi, and Yoshinori Onose
Nature Communications, Vol.15, (2024) pp. 1999-1-8 [Press Release]
“Quantitative measurement of figure of merit for transverse thermoelectric conversion in Fe/Pt metallic multilayers”
Takumi Yamazaki, Takamasa Hirai, Takashi Yagi, Yuichiro Yamashita, Ken-ichi Uchida, Takeshi Seki, and Koki Takanashi
Phys. Rev. Applied, Vol.21, (2024) pp. 024039-1-11
[Editors' Suggestion]
“Bipolarity of large anomalous Nernst effect in Weyl magnet-based alloy films”
Shun Noguchi, Kohei Fujiwara, Yuki Yanagi, Michi-To Suzuki, Takamasa Hirai, Takeshi Seki, Ken-ichi Uchida, and Atsushi Tsukazaki
Nature Physics, Vol.20, (2024) pp. 254-260 [Press Release]
“Uniaxial magnetic anisotropy of L10-FeNi films with island structures on LaAlO3(110) substrates by nitrogen insertion and topotactic extraction”
Takahiro Nishio, Keita Ito, Hiroaki Kura, Koki Takanashi, and Hideto Yanagihara
Journal of Alloys and Compounds, Vol.976, (2024) pp. 172992-1-8
2023
“Effect of multilayering and crystal orientation on spin-orbit torque efficiency in Ni/Pt layer stacking”
A. Sud, Y.-C. Lau, J. Brierley, H. Kurebayashi, and T. Seki
Phys. Rev. Mater., Vol.7, (2023) pp. 124410-1-13
“Perspective on spin-based wave-parallel computing”
Makoto Kohda, Takeshi Seki, Yasushi Yuminaka, Tetsuya Uemura, Keito Kikuchi and Gian Salis
Appl. Phys. Lett., Vol.123, (2023) pp. 190502-1-18
[Featured Article]
“Antiferromagnetic Films and Their Applications (Topical Review)”
Atsufumi Hirohata, David C. Lloyd, Takahide Kubota, Takeshi Seki, Koki Takanashi, Hiroaki Sukegawa, Zhenchao Wen, Seiji Mitani, and Hiroki Koizumi
IEEE Access., Vol.11, (2023) pp. 117443-117459
“Impact of epitaxial strain relaxation on ferromagnetism in a freestanding La2/3Sr1/3MnO3 membrane”
Ryuji Atsumi, Junichi Shiogai, Takumi Yamazaki, Takeshi Seki, Kohei Ueda, and Jobu Matsuno
Jpn. J. Appl. Phys., Vol.62, (2023) pp. 100902-1-5
“Magnetic layer thickness influence on magnetoelastic properties anisotropy in Co2Fe0.4Mn0.6Si Heusler alloy thin films”
Adam Nabiałek, Oleksandr Chumak, Takeshi Seki, Koki Takanashi, Lech T. Baczewski, and Henryk Szymczak
IEEE Trans. Magn., Vol.59, (2023) pp. 2501405-1-6
“Influence of the strain effect on magnetocrystalline anisotropy in Co2Fe0.4Mn0.6Si Heusler alloys”
A. Nabiałek, O. M. Chumak, P. Aleshkevych, J. Z. Domagala, A. Pacewicz, B. Salski, J. Krupka, T. Seki, K. Takanashi, L. T. Baczewski, and H. Szymczak
Sci. Rep., Vol.13, (2023) pp. 17016-1-9
“Intercorrelated anomalous Hall and spin Hall effect in kagome-lattice Co3Sn2S2-based shandite films”
Yong-Chang Lau, Junya Ikeda, Kohei Fujiwara, Akihiro Ozawa, Jiaxin Zheng, Takeshi Seki, Kentaro Nomura, Liang Du, Quansheng Wu, Atsushi Tsukazaki, and Koki Takanashi
Phys. Rev. B, Vol.108, (2023) pp. 064429-1-11
[Editors’ Suggestion] [Press Release]
“Influence of epitaxial growth on spin current transmission of NiO films”
Takumi Yamazaki, Takeshi Seki, Takahide Kubota, and Koki Takanashi
Appl. Phys. Express, Vol.16, (2023) pp. 083003-1-4
“Magnetization switching process by dual spin–orbit torque in interlayer exchange-coupled systems”
Hiroto Masuda, Yuta Yamane, Takeshi Seki, Klaus Raab, Takaaki Dohi, Rajkumar Modak, Ken-ichi Uchida, Jun’ichi Ieda, Mathias Kläui, and Koki Takanashi
Appl. Phys. Lett., Vol.122, (2023) pp. 162402-1-7
“Lattice constants and magnetism of L10-ordered FePt under high pressure”
S. Sawada, K. Okai, H. Fukui, R. Takahashi, N. Ishimatsu, H. Maruyama, N. Kawamura, S. Kawaguchi, N. Hirao, T. Seki, K. Takanashi, S. Ohmura, and H. Wadati
Appl. Phys. Lett., Vol.122, (2023) pp. 152406-1-5
“Enhancement of spin-charge conversion efficiency for Co3Sn2S2 across transition from paramagnetic to ferromagnetic phase”
Takeshi Seki, Yong-Chang Lau, Junya Ikeda, Kohei Fujiwara, Akihiro Ozawa, Satoshi Iihama, Kentaro Nomura, and Atsushi Tsukazaki
Phys. Rev. Research, Vol.5, (2023) pp. 013222-1-14
“Current-induced crystallisation in a Heusler-alloy-based giant magnetoresistive junction for neuromorphic potentiation”
Zhenyu Zhou, William Frost, David C. Lloyd, Takeshi Seki, Takahide Kubota, Rafael Ramos, Eiji Saitoh, Koki Takanashi, and Atsufumi Hirohata
J. Magn. Magn. Mater., Vol.571, (2023) pp. 170575-1-5.
“Fabrication of L10-ordered FeNi films by denitriding FeNiN(001) and FeNiN(110) films”
Keita Ito, Takumi Ichimura, Masahiro Hayashida, Takahiro Nishio, Sho Goto, Hiroaki Kura, Ryusei Sasaki, Masahito Tsujikawa, Masafumi Shirai, Tomoyuki Koganezawa, Masaki Mizuguchi, Yusuke Shimada, Toyohiko J. Konno, Hideto Yanagihara, and Koki Takanashi
Journal of Alloys and Compounds, Vol.946, (2023) pp. 169450-1-10.
“Anomalous Nernst effect in epitaxially grown Fe4−xNixN films”
Weida Yin, Keita Ito, Yusuke Tsubowa, Masahito Tsujikawa, Masafumi Shirai, and Koki Takanashi
AIP Advances, Vol.13, (2023) pp. 025243-1-6.
“Superconducting fluctuation effect on epitaxially layered films of superconductor NbN and half-metallic Heusler alloy Co2MnSi”
Iduru Shigeta, Shuta Oku, Takahide Kubota, Shojiro Kimura, Takeshi Seki, Bunju Shinozaki, Satoshi Awaji, Koki Takanashi, and Masahiko Hiroi
AIP Advances, Vol.13, (2023) pp. 025116-1-5.
2022
“Electrical detection of domain evolution in magnetic Weyl semimetal Co3Sn2S2 submicrometer-wide wire devices”
Junichi Shiogai, Junya Ikeda, Kohei Fujiwara, Takeshi Seki, Koki Takanashi, and Atsushi Tsukazaki
Phys. Rev. Mater., Vol.6, (2022) pp. 114203-1-9.
“Sm-Co-based amorphous alloy films for zero-field operation of transverse thermoelectric generation”
Rajkumar Modak, Yuya Sakuraba, Takamasa Hirai, Takashi Yagi, Hossein Sepehri-Amin, Weinan Zhou, Hiroto Masuda, Takeshi Seki, Koki Takanashi, Tadakatsu Ohkubo and Ken-ichi Uchida
SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS, Vol.23, (2022) pp. 767-782.
“Enhancement of the anomalous Nernst effect in epitaxial Fe4N films grown on SrTiO3(001) substrates with oxygen deficient layers”
Keita Ito, Jian Wang, Yusuke Shimada, Himanshu Sharma, Masaki Mizuguchi, and Koki Takanashi
J. Appl. Phys., Vol.132, (2022) pp. 133904-1-7.
“Perpendicularly magnetized epitaxial Co/Ni multilayers grown on Ru (0001) layers by alternate monoatomic layer deposition”
Keita Ito, Naoto Kikuchi, Takeshi Seki, and Koki Takanashi
J. Magn. Magn. Mater., Vol. 563, (2022) pp.169908-1-6.
“Elemental Doping and Interface Effects on Spin–Orbit Torques in CoSi-Based Topological Semimetal Thin Films”
Ke Tang, Zhenchao Wen, Takeshi Seki, Hiroaki Sukegawa, and Seiji Mitani
Adv. Mater. Interfaces, Vol. XX, (2022) pp. 2201332-1-7.
“Anisotropy of magnetoelastic properties in epitaxial Co2FexMn1−xSi Heusler alloy thin films”
A. Nabiałek, O. Chumak, A. Lynnyk, J. Z. Domagała, A. Pacewicz, B. Salski, J. Krupka, T. Yamamoto, T. Seki, K. Takanashi, L. T. Baczewski, and H. Szymczak
Phys. Rev. B, Vol. 106, (2022) pp.054406-1-11.
“Thickness dependence of anomalous Hall and Nernst effects in Ni-Fe thin films”
Takumi Yamazaki, Takeshi Seki, Rajkumar Modak, Keita Nakagawara, Takamasa Hirai, Keita Ito, Ken-ichi Uchida, and Koki Takanashi
Phys. Rev. B, Vol. 105, (2022) pp.214416-1-9.
“Large Antisymmetric Interlayer Exchange Coupling Enabling Perpendicular Magnetization Switching by an In-Plane Magnetic Field”
Hiroto Masuda, Takeshi Seki, Yuta Yamane, Rajkumar Modak, Ken-ichi Uchida, Jun’ichi Ieda, Yong-Chang Lau, Shunsuke Fukami, and Koki Takanashi
Phys. Rev. Appl., Vol. 17, (2022) pp.054036-1-9.
“All-Optical Detection of Spin Pumping and Giant Interfacial Spin Transparency in Co2Fe0.4Mn0.6Si/Pt Heterostructure”
Koustuv Dutta, Surya N Panda, Takeshi Seki, Santanu Pan, Koki Takanashi, and Anjan Barman
Adv. Quantum. Technol., Vol. 5, (2022) pp.2200033-1-10.
“Magnetoelastic anisotropy in Heusler-type Mn2−δCoGa1+δ films”
Takahide Kubota, Daichi Takano, Yohei Kota, Shaktiranjan Mohanty, Keita Ito, Mitsuhiro Matsuki, Masahiro Hayashida, Mingling Sun, Yukiharu Takeda, Yuji Saitoh, Subhankar Bedanta, Akio Kimura, and Koki Takanashi
Phys. Rev. Mater., Vol. 6, (2022) pp.044405-1-12.
“Strain-Induced Large Anomalous Nernst Effect in Polycrystalline Co2MnGa/AlN Multilayers”
Jian Wang, Yong-Chang Lau, Weinan Zhou, Takeshi Seki, Yuya Sakuraba, Takahide Kubota, Keita Ito, and Koki Takanashi
Adv. Electron. Mater., Vol. 8, (2022) pp.2101380-1-8.
Reviews and Books
2024
解説:薄膜の垂直磁気異方性
高梨弘毅、関剛斎
まぐね、Vol. 19, (2024) pp. 100-106.
2023
解説:新しいエネルギー変換技術としての磁気熱電効果:異常ネルンスト効果
関剛斎
電気学会誌, Vol. 143, (2023) pp. 710-713.
解説:反強磁性結合人工格子の新展開 –反対称層間交換結合を中心にして–
関剛斎、増田啓人、高梨弘毅
固体物理、Vol. 58, (2023) pp. 9-20.
著書:正常ホール効果と異常ホール効果
関剛斎
エヌ・ティー・エス「スピントロニクスハンドブック−基礎から応用まで−」第4章, 第3節 (2023) pp. 75-79.
解説:電流−スピン流−熱流変換材料の現状と課題
関剛斎
まてりあ、Vol. 62, (2023) pp. 85-92.
2022
解説:永久磁石応用を目指したトポタクティック脱窒素法によるL10型FeNi規則合金の創製
伊藤啓太、高梨弘毅、藏裕彰
まぐね、Vol. 17, (2022) pp. 82-88.
解説:金属人工格子ルネサンス
高梨弘毅、関剛斎
まぐね、Vol. 17, (2022) pp. 4-11.
2021
著書:"Spin-transfer torque and related phenomena"
Takeshi Seki and Koki Takanashi
Nanomagnetic Materials -Fabrication, Characterization and Application (Eds: Akinobu Yamaguchi, Atsufumi Hirohata, and Bethanie Stadler, Elsevier, 2021) pp. 345-358.