
介川 裕章 (SUKEGAWA, Hiroaki)
磁性・スピントロニクス材料研究センター スピントロニクスグループ グループリーダー
筑波大学 NIMS連係大学院 数理物質科学研究群 准教授
Email: SUKEGAWA.Hiroaki[at]nims.go.jp
Here's English page
【ニュース・トピック】
- 2023/03 《NIMSプレスリリース》素子「界面」の高度な制御で世界最高の磁気抵抗特性631%を達成
- 2025/07 《NIMSプレスリリース》高エントロピー酸化物で低抵抗・高性能TMR素子を実現 ~大容量磁気ストレージでスマート社会を支える新材料~
- 2026/05 《デモ機公開》強磁性トンネル接合(MTJ、TMR素子)を用いてフルカラーLEDを操作
自己紹介
2007年3月東北大工学研究科にて博士(工学)を取得し、その後、2007年4月物質・材料研究機構 研究員、2014年主任研究員、 2018年主幹研究員を経て、2023年に現職(スピントロニクスグループ グループリーダー)です。2026年に筑波大学NIMS連係大学院・准教授にも着任しました。専門は磁性薄膜成長、スピントロニクス素子・材料です。学部4年生の2002年からトンネル磁気抵抗効果の研究を続けています。 これまで、MgAl2O4などのスピネル酸化物が磁気トンネル接合(MTJ)のバリア層材料となることを発見し、 その後、大きなトンネル磁気抵抗比(TMR比)比が得られることを示してきました。 また、2023年には室温におけるTMR比の最大レコードを更新する631%を実現しました【 詳細】。
下の図は室温TMR比のバリア材料ごとの推移を示しています。MgOバリア、スピネルバリア、 ガリウムスピネルバリアではNIMSスピントロニクスグループが最高値を保持しています(2026年現在)。
室温TMR比の推移とスピントロニクスグループの報告値
略歴
専門分野
研究紹介
所属学会
学会委員歴
受賞歴
主要論文
All publications (ResearchGate)- Cong He, Zhenchao Wen, Jun Okabayashi, Yoshio Miura, Tianyi Ma, Tadakatsu Ohkubo, Takeshi Seki, Hiroaki Sukegawa and Seiji Mitani,
"Evidence for single variant in altermagnetic RuO2(101) thin films"
Nat. Commun. 16, 8235-1~9 (2025).
Open access
《プレスリリース》AI時代を支える新磁性体、二酸化ルテニウム薄膜の「交代磁性」を実証 ~AI・データセンター向け高速・高密度メモリ開発に期待~

- R. R. Sihombing, T. Scheike, J. Uzuhashi, H. Yasufuku, T. Ohkubo, Z. Wen, S. Mitani, and H. Sukegawa (corresponding author),
"High entropy oxide epitaxial films with interface perpendicular magnetic anisotropy and tunnel magnetoresistance effect toward spintronic applications"
Mater. Today 88, 12-23 (2025).
Open access
《NIMSプレスリリース》高エントロピー酸化物で低抵抗・高性能TMR素子を実現 ~大容量磁気ストレージでスマート社会を支える新材料~

- Keisuke Masuda, Thomas Scheike, Hiroaki Sukegawa, Yusuke Kozuka, Seiji Mitani, and Yoshio Miura,
"Theory for tunnel magnetoresistance oscillation"
Phys. Rev. B 111, L220406-1~6 (2025).
Selected as Editor's suggestion
Open access
《プレスリリース》 トンネル磁気抵抗(TMR)に対する新理論を提案 ~TMR比向上の鍵「TMR振動」の解明に前進~- - Taisuke Horaguchi, Cong He, Zhenchao Wen, Hayato Nakayama, Tadakatsu Ohkubo, Seiji Mitani, Hiroaki Sukegawa, Junji Fujimoto, Kazuto Yamanoi, Mamoru Matsuo, and Yukio Nozaki,
"Nanometer-thick Si/Al gradient materials for spin torque generation"
Sci. Adv. 11, eadr9481 (2025).
Open access - 詳細はこちら
Rombang Rizky Sihombing, Thomas Scheike, Jun Uzuhashi, Tadakatsu Ohkubo, Zhenchao Wen, Seiji Mitani, and Hiroaki Sukegawa (corresponding author),
"Enhanced tunnel magnetoresistance of Fe/MgGa2O4/Fe(001) magnetic tunnel junctions by interface-tuning with atomic scale MgO insertion layers"
Appl. Phys. Lett. 126, 022407-1~7 (2025).
Selected as Editor's Pick
Open access - 詳細はこちら
Jieyuan Song (corresponding author), Thomas Scheike, Cong He, Zhenchao Wen, Tadakatsu Ohkubo, Kwangseok Kim, Hiroaki Sukegawa (corresponding author), and Seiji Mitani,
"Incommensurate superlattice modulation surviving down to an atomic scale in sputter-deposited Co/Pt(111) epitaxial multilayered films"
APL Mater. 12, 101120-1~7 (2024).
Open access
- Cong He, Keisuke Masuda, Jieyuan Song, Thomas Scheike, Zhenchao Wen; Yoshio Miura, Tadakatsu Ohkubo, Kazuhiro Hono, Seiji Mitani, and Hiroaki Sukegawa,
"Nano-crystal domains in Co-based fcc(111) epitaxial magnetic junctions and their impact on tunnel magnetoresistance"
Acta Mater. 261, 119394-1~14 (2023). - 詳細はこちら
Thomas Scheike, Zhenchao Wen, Hiroaki Sukegawa (corresponding author), and Seiji Mitani,
"631% room temperature tunnel magnetoresistance with large oscillation effect in CoFe/MgO/CoFe(001) junctions"
Appl. Phys. Lett. 122, 112404-1~6 (2023).
Selected as Featured Article
Open access
《NIMSプレスリリース》素子「界面」の高度な制御で世界最高の磁気抵抗特性を達成 - Thomas Scheike, Zhenchao Wen, Hiroaki Sukegawa (corresponding author), and Seiji Mitani,
"Enhanced tunnel magnetoresistance in Fe/Mg4Al-Ox/Fe(001) magnetic tunnel junctions"
Appl. Phys. Lett. 120, 032404-1~4 (2022).
Selected as Editor's Pick
Open access - Muftah Al-Mahdawi, Qingyi Xiang, Yoshio Miura, Mohamed Belmoubarik, Keisuke Masuda, Shinya Kasai, Hiroaki Sukegawa, and Seiji Mitani,
"Quantum-well tunneling anisotropic magnetoresistance above room temperature"
Phys. Rev. B 103, L180408-1~6 (2021). - Thomas Scheike, Qingyi Xiang, Zhenchao Wen, Hiroaki Sukegawa (corresponding author), Tadakatsu Ohkubo, Kazuhiro Hono, and Seiji Mitani,
"Exceeding 400% tunnel magnetoresistance at room temperature in epitaxial Fe/MgO/Fe(001) spin-valve-type magnetic tunnel junctions"
Appl. Phys. Lett. 118, 042411-1~6 (2021).
Selected as Featured Article
Selected as Scilight "Researchers double room temperature tunnel magnetoresistance ratios of Fe/MgO/Fe" - Q. Y. Xiang, H. Sukegawa, M. Belmoubarik, M. Al-Mahdawi, T. Scheike, S. Kasai, Y. Miura, and S. Mitani,
"Realizing Room-Temperature Resonant Tunnel Magnetoresistance in Cr/Fe/MgAl2O4 Quasi-Quantum Well Structures"
Adv. Sci. 6, 1901438-1~7 (2019). - Ikhtiar, Hiroaki Sukegawa (corresponding author), Xiandong Xu, Mohamed Belmoubarik, Hwachol Lee, Shinya Kasai, and Kazuhiro Hono,
"Giant tunnel magnetoresistance in polycrystalline magnetic tunnel junctions with highly-textured MgAl2O4(001) based barriers"
Appl. Phys. Lett. 112, 022408-1~5 (2018).
Selected as Featured article - Hiroaki Sukegawa, Yushi Kato, Mohamed Belmoubarik, P.-H. Cheng, Tadaomi Daibou, Naoharu Shimomura, Yuuzo Kamiguchi, Junichi Ito, Hiroaki Yoda, Tadakatsu Ohkubo, Seiji Mitani, and Kazuhiro Hono,
"MgGa2O4 spinel barrier for magnetic tunnel junctions: Coherent tunneling and low barrier height"
Appl. Phys. Lett. 110, 122404-1~5 (2017).
Selected as AIP in the news - Hiroaki Sukegawa, Jason Paul Hadorn, Zhenchao Wen, Tadakatsu Ohkubo, Seiji Mitani, and Kazuhiro Hono,
"Perpendicular magnetic anisotropy at lattice-matched Co2FeAl/MgAl2O4(001) epitaxial interfaces"
Appl. Phys. Lett. 110, 112403-1~4 (2017). - Thomas Scheike, Hiroaki Sukegawa (corresponding author), Koichiro Inomata, Tadakatsu Ohkubo, Kazuhiro Hono, and Seiji Mitani,
"Chemical ordering and large tunnel magnetoresistance in Co2FeAl/MgAl2O4/Co2FeAl(001) junctions"
Appl. Phys. Express 9, 053004-1~4 (2016).
Selected as Spotlights2016 - Mohamed Belmoubarik, Hiroaki Sukegawa (corresponding author), Tadakatsu Ohkubo, Seiji Mitani, and Kazuhiro Hono,
"MgAl2O4(001) based magnetic tunnel junctions made by direct sputtering of a sintered spinel target"
Appl. Phys. Lett. 108, 132404-1~5 (2016).
Selected as APL Editor's pick - Zhenchao Wen, Hiroaki Sukegawa, Takao Furubayashi, Jungwoo Koo, Koichiro Inomata, Seiji Mitani, Jason Paul Hadorn, Tadakatsu Ohkubo, and Kazuhiro Hono,
"A 4-Fold-Symmetry Hexagonal Ruthenium for Magnetic Heterostructures Exhibiting Enhanced Perpendicular Magnetic Anisotropy and Tunnel Magnetoresistance"
Adv. Mater. 26, 6483-6490 (2014). - Hiroaki Sukegawa, Yoshio Miura, Shingo Muramoto, Seiji Mitani, Tomohiko Niizeki, Tadakatsu Ohkubo, Kazutaka Abe, Masafumi Shirai, Koichiro Inomata, and Kazuhiro Hono,
"Enhanced tunnel magnetoresistance in a spinel oxide barrier with cation site disorder",
Phys. Rev. B 86, 184401-1~5 (2012). - Hiroaki Sukegawa, Huixin Xiu, Tadakatsu Ohkubo, Takao Furubayashi, Tomohiko Niizeki, Wenhong Wang, Shinya Kasai, Seiji Mitani, Koichiro Inomata, and Kazuhiro Hono,
"Tunnel Magnetoresistance with Improved Bias Voltage Dependence in Lattice-Matched Fe/Spinel MgAl2O4/Fe(001) Junctions"
Appl. Phys. Lett. 96, 212505-1~3 (2010). - R. Shan, H. Sukegawa, W. H. Wang, M. Kodzuka, T. Furubayashi, T. Ohkubo, S. Mitani, K. Inomata, and K. Hono,
"Demonstration of Half-Metallicity in Fermi-Level-Tuned Heusler Alloy Co2FeAl0.5Si0.5 at Room Temperature"
Phys. Rev. Lett. 102, 246601-1~4 (2009). - H. Sukegawa, S. Nakamura, A. Hirohata, N. Tezuka and K. Inomata,
"Significant Magnetoresistance Enhancement Due to a Cotunneling Process in a Double Tunnel Junction with Single Discontinuous Ferromagnetic Layer Insertion"
Phys. Rev. Lett. 94, 068304-1~4 (2005).
- Yukio Nozaki, Hiroaki Sukegawa, Shinichi Watanabe, Seiji Yunoki, Taisuke Horaguchi, Hayato Nakayama, Kazuto Yamanoi, Zhenchao Wen, Cong He, Jieyuan Song, Tadakatsu Ohkubo, Seiji Mitani, Kazuki Maezawa, Daichi Nishikawa, Shun Fujii, Mamoru Matsuo, Junji Fujimoto, and Sadamichi Maekawa,,
"Gyro-spintronic material science using vorticity gradient in solids"
Sci. Technol. Adv. Mater. 26, 2428153-1~39 (2025). - Kelvin Elphick, William Frost, Marjan Samiepour, Takahide Kubota, Koki Takanashi, Hiroki Sukegawa, Seiji Mitani, and Atsufumi Hirohata,
"Heusler alloys for spintronic devices: review on recent development and future perspectives"
Sci. Technol. Adv. Mater. 22, 235-271 (2021). - M. Coll, J. Fontcuberta, M. Althammer, M. Bibes, H. Boschker, A. Calleja, G. Cheng, M. Cuoco, R. Dittmann, B. Dkhil, I. El Baggari, M. Fanciulli,
I. Fina, E. Fortunato, C. Frontera, S. Fujita, V. Garcia, S.T.B. Goennenwein, C.-G. Granqvist, J. Grollier, R. Gross, A. Hagfeldt, G. Herranz, K. Hono,
E. Houwman, M. Huijben, A. Kalaboukhov, D.J. Keeble, G. Koster, L.F. Kourkoutis, J. Levy, M. Lira-Cantu, J.L. MacManus-Driscoll, J. Mannhart, R. Martins,
S. Menzel, T. Mikolajick, M. Napari, M.D. Nguyen, G. Niklasson, C. Paillard, S. Panigrahi, G. Rijnders, F. Sanchez, P. Sanchis, S. Sanna, D.G. Schlom,
U. Schroeder, K.M. Shen, A. Siemon, M. Spreitzer, H. Sukegawa, R. Tamayo, J. van den Brink, N. Pryds, and F.M. Granozio,
"Towards Oxide Electronics: a Roadmap"
Appl. Surf. Sci. 482, 1~92 (2019).
Open access
- Atsufumi Hirohata, Hiraoki Sukegawa, Hideto Yanagihara, Igor Zutic, Takeshi Seki, Shigemi Mizukami, and Raja Swaminathan,
"Roadmap for Emerging Materials for Spintronic Device Applications"
IEEE Trans. Magn. 51, 0800511-1~11 (2015).
Open access
- H. Sukegawa, Z. C. Wen, S. Kasai, K. Inomata, and S. Mitani,
"Spin transfer torque switching and perpendicular magnetic anisotropy in full Heusler alloy Co2FeAl-based tunnel junctions"
SPIN 4, 1440023-1~15 (2014).
Open access
STAM Altmetrics Award for 2021
Open access



