Investigation of unconventional superconducting phenomena induced in ferromagnetic semiconductors

• Project/Area Number: 17K05492
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Condensed matter physics I
• Research Institution: The University of Tokyo
• Principal Investigator: Nakamura Taketomo 東京大学, 物性研究所, 助教 (50636503)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2019: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2018: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2017: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
• Keywords: 超伝導接合 / 半導体 / 磁性 / ジョセフソン効果 / 近接効果 / スピン三重項超伝導 / 強磁性体 / アンドレーエフ反射 / スピンフィルター / スピン物性 / 磁性半導体 / 超伝導材料・素子 / スピンエレクトロニクス / 半導体物性 / メゾスコピック系 / 低温物性

Outline of Final Research Achievements

We fabricated superconducting junctions with a ferromagnetic semiconductor (In,Fe)As and conventional superconductor Nb. We observed that the resistance reaches zero down to the lowest temperature of 0.1 K. The current-voltage characteristics of the junction evidenced that the zero resistance originates from the Josephson effect. This is the first observation of the supercurrent in ferromagnetic semiconductors. We also measured the field dependence and temperature dependence of the critical current and demonstrated that the induced superconductivity in the ferromagnetic semiconductor is due to the spin-triplet Cooper pairing.

Academic Significance and Societal Importance of the Research Achievements

本研究はこれまで困難であった強磁性半導体中での超伝導近接効果と有限の超伝導電流の観測に世界で初めて成功した。強磁性半導体は強磁性金属と異なり、電場によって磁性を大きく変えることができるため、これを用いた超伝導接合では超伝導電流のスピン状態を電場で制御する、これまでにない画期的な超伝導デバイスの実現も期待できる。強磁性半導体はスピントロニクス材料としても有力であり、スピン三重項超伝導のスピントロニクスへの応用可能性も示すことができた。

Research Products

• [Journal Article] Room-temperature quantum spin Hall phase in laser-patterned few-layer 1T’- MoS2 (2020)
  • Author(s): N. Katsuragawa, M. Nishizawa, T. Nakamura, T. Inoue, S. Pakdel, S. Maruyama, S. Katsumoto, J. J. Palacios, J. Haruyama
  • Journal Title: Communications Materials Volume: －
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Topological Insulating States in Graphene with Low-Amount Nanoparticle Decoration (2019)
  • Author(s): 春山 純志、勝本 信吾、中村 壮智
  • Journal Title: Butsuri Volume: 74 Issue: 12 Pages: 839-844
  • DOI: 10.11316/butsuri.74.12_839
  • NAID: 130007843282
  • ISSN: 0029-0181, 2423-8872
  • Year and Date: 2019-12-05
  • Peer Reviewed
• [Journal Article] Laser-Beam-Patterned Topological Insulating States on Thin Semiconducting MoS2 (2019)
  • Author(s): H. Mine, A. Kobayashi, T. Nakamura, T. Inoue, S. Pakdel, D. Marian, E. Gonzalez-Marin, S. Maruyama, S. Katsumoto, A. Fortunelli, J. J. Palacios, and J. Haruyama
  • Journal Title: Physical Review Letters Volume: 123 Issue: 14 Pages: 146803-146803
  • DOI: 10.1103/physrevlett.123.146803
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Evidence for Spin-Triplet Electron Pairing in the Proximity-Induced Superconducting State of an Fe-Doped InAs Semiconductor (2019)
  • Author(s): Nakamura Taketomo, Anh Le Duc, Hashimoto Yoshiaki, Ohya Shinobu, Tanaka Masaaki, and Katsumoto Shingo
  • Journal Title: Physical Review Letters Volume: 122 Issue: 10 Pages: 107001-107001
  • DOI: 10.1103/physrevlett.122.107001
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Spin Filtering Magnetoresistance in Double‐Well Resonant Structures (2019)
  • Author(s): Nakamura Taketomo, Hashimoto Yoshiaki, Ke Tong, and Katsumoto Shingo
  • Journal Title: physica status solidi (b) Volume: なし Issue: 6 Pages: 1800560-1800560
  • DOI: 10.1002/pssb.201800560
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Evidence for a quantum spin Hall phase in graphene decorated with Bi2Te3 nanoparticles (2018)
  • Author(s): Hatsuda K.、Mine H.、Nakamura T.、Li J.、Wu R.、Katsumoto S.、Haruyama J.
  • Journal Title: Science Advances Volume: 4 Issue: 11
  • DOI: 10.1126/sciadv.aau6915
  • Peer Reviewed / Open Access
• [Journal Article] 半導体の電気伝導におけるZitterbewegung（ジグザグ運動） (2018)
  • Author(s): 中村壮智, 勝本信吾
  • Journal Title: 日本物理学会誌 Volume: 73 Pages: 776-781
  • NAID: 130007652830
  • Peer Reviewed
• [Journal Article] Proximity-Induced Superconductivity in a Ferromagnetic Semiconductor (In,Fe)As (2018)
  • Author(s): Taketomo Nakamura, Le Duc Anh, Yoshiaki Hashimoto, Yu Iwasaki, Shinobu Ohya, Masaaki Tanaka and Shingo Katsumoto
  • Journal Title: Journal of Physics: Conference Series Volume: 969 Pages: 012036-012036
  • DOI: 10.1088/1742-6596/969/1/012036
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] Spin Blockade and Magnetoresistance in Double QuantumWell Diode with Inverted Electric Field (2019)
  • Author(s): Yoshiaki Hashimoto, Tong Ke, Taketomo Nakamura, and Shingo Katsumoto
  • Organizer: Compound Semiconductor Week 2019
  • Int'l Joint Research
• [Presentation] Control of electron spin at spin-resolved quantum Hall edges (2019)
  • Author(s): Takase Shimizu, Yoshiaki Hashimoto, Taketomo Nakamura, Akira Endo, and Shingo Katsumoto
  • Organizer: Compound Semiconductor Week 2019
  • Int'l Joint Research
• [Presentation] The Josephson effect in InAs quantum wells with the spin Hall effect (2019)
  • Author(s): Taketomo Nakamura, Yoshiaki Hashimoto, and Shingo Katsumoto
  • Organizer: Compound Semiconductor Week 2019
  • Int'l Joint Research
• [Presentation] Superconductor connection to InAs two-dimensional electrons with accumulation edges (2019)
  • Author(s): Makoto Onizaki, Yoshiaki Hashimoto, Taketomo Nakamura, and Shingo Katsumoto
  • Organizer: Compound Semiconductor Week 2019
  • Int'l Joint Research
• [Presentation] Anomalous suppression of the Josephson effect in InAs 2D electron systems due to the spin Hall effect (2019)
  • Author(s): Taketomo Nakamura, Yoshiaki Hashimoto, and Shingo Katsumoto
  • Organizer: Spintech X
  • Int'l Joint Research
• [Presentation] Spin manipulation in quantum Hall edge states through spin-orbit interaction (2019)
  • Author(s): T.Shimizu, Y.Hashimoto, T.Nakamura, A. Endo, and S. Katsumoto
  • Organizer: Spintech X
  • Int'l Joint Research
• [Presentation] トレンチ型サイドゲート付き超伝導/InAs二次元電子ガス/超伝導接合の輸送特性 (2019)
  • Author(s): 鬼嵜誠, 橋本義昭, 中村壮智, 勝本信吾
  • Organizer: 日本物理学会 2019年秋季大会
• [Presentation] Ti/MoS2界面における超伝導状態の磁気履歴効果 (2019)
  • Author(s): 相川夕美花, 石黒亮輔, 遠藤彰, 中村壮智, 橋本義昭, 清水貴勢, 津村公平, 柏谷聡, 高柳英明, 勝本信吾
  • Organizer: 日本物理学会 2019年秋季大会
• [Presentation] The Josephson effect on the multiterminal junctions of InAs 2D electron system (2019)
  • Author(s): T. Nakamura
  • Organizer: 3rd EPiQS-TMS alliance workshop on Topological Phenomena in Quantum Materials
  • Int'l Joint Research / Invited
• [Presentation] Side gate control of supercurrent in an InAs quantum well (2019)
  • Author(s): M. Onizaki, Y. Hashimoto, T. Nakamura, S. Katsumoto
  • Organizer: 3rd EPiQS-TMS alliance workshop on Topological Phenomena in Quantum Materials
  • Int'l Joint Research
• [Presentation] Landau-Zener mixing of spin-resolved quantum Hall edge channels (2019)
  • Author(s): T.Shimizu, Y.Hashimoto, T.Nakamura, A. Endo, and S. Katsumoto
  • Organizer: 3rd EPiQS-TMS alliance workshop on Topological Phenomena in Quantum Materials
  • Int'l Joint Research
• [Presentation] Supercurrent Reduction through Voltage-control of Kinetic Phase (2019)
  • Author(s): M. Onizaki, Y. Hashimoto, T. Nakamura, S. Katsumoto
  • Organizer: International School and Symposium on Nanoscale Transport and phoTonics 2019
  • Int'l Joint Research
• [Presentation] The Josephson Effect with Transverse Spin Current in an InAs Quantum Well (2019)
  • Author(s): T. Nakamura
  • Organizer: 14th Asia Pacific Physics Conference
  • Int'l Joint Research / Invited
• [Presentation] Anomalous reduction of the supercurrent due to the electric field gradient (2019)
  • Author(s): Taketomo Nakamura, M. Onizaki, Y. Hashimoto, and S. Katsumoto
  • Organizer: International Conference on Topological Materials Science 2019
  • Int'l Joint Research
• [Presentation] Gate control of intra-Landau level transition and observation of spin precession at quantum Hall state (2019)
  • Author(s): Takase SHIMIZU, Yoshiaki HASHIMOTO, Taketomo NAKAMURA, Akira ENDO, and Shingo KATSUMOTO
  • Organizer: MATERIALS RESEARCH MEETING 2019
  • Int'l Joint Research
• [Presentation] Spin-Blockade and Rashba-Resonance in a Double Quantum Well Diode (2019)
  • Author(s): Taketomo NAKAMURA, Yoshiaki HASHIMOTO, and Shingo KATSUMOTO
  • Organizer: MATERIALS RESEARCH MEETING 2019
  • Int'l Joint Research
• [Presentation] In-plane field and current dependence of the Josephson effect in Nb/InAs/Nb junctions (2019)
  • Author(s): T. Nakamura, Y. Hashimoto, and S. Katsumoto
  • Organizer: Topological Phases and Functionality of Correlated Electron Systems 2019
  • Int'l Joint Research
• [Presentation] Supercurrent on accumulation edges of an InAs quantum well (2019)
  • Author(s): M. Onizaki, T. Nakamura, Y. Hashimoto, and S. Katsumoto
  • Organizer: Topological Phases and Functionality of Correlated Electron Systems 2019
  • Int'l Joint Research
• [Presentation] Control of electron spin through quantum Hall edge-spin entanglement (2019)
  • Author(s): T. Shimizu, Y. Hashimoto, T. Nakamura, A. Endo, and S. Katsumoto
  • Organizer: Topological Phases and Functionality of Correlated Electron Systems 2019
  • Int'l Joint Research
• [Presentation] 電流注入によるジョセフソン効果の制御 (2019)
  • Author(s): 中村壮智
  • Organizer: 日本物理学会第74回年次大会
  • Invited
• [Presentation] 量子ホールエッジ状態間の電子スピン非断熱遷移と位相の独立制御 (2019)
  • Author(s): 清水貴勢, 橋本義昭, 中村壮智, 遠藤彰, 勝本信吾
  • Organizer: 日本物理学会第74回年次大会
• [Presentation] n-i-p-i-n 三重障壁構造におけるスピンブロッケード (2019)
  • Author(s): 橋本義昭, 中村壮智, 勝本信吾
  • Organizer: 日本物理学会第74回年次大会
• [Presentation] Ti/ MoS2界面における輸送特性 (2019)
  • Author(s): 相川夕美花, 遠藤彰, 中村壮智, 清水貴勢, 成田智絵, 津村公平, 柏谷聡, 高柳英明, 勝本信吾, 石黒亮輔
  • Organizer: 日本物理学会第74回年次大会
• [Presentation] 量子ポイントコンタクト付き超伝導/InAs二次元電子ガス/超伝導接合の伝導特性 (2019)
  • Author(s): 鬼嵜誠, 橋本義昭, 中村壮智, 勝本信吾
  • Organizer: 日本物理学会第74回年次大会
• [Presentation] The Josephson effect in Nb/InAs/Nb junctions under in-plane magnetic fields (2018)
  • Author(s): T. Nakamura, Y. Hashimoto, and S. Katsumoto
  • Organizer: 34th International Conference on the Physics of Semiconductors
  • Int'l Joint Research
• [Presentation] In-plane resonant spin-filtering with Rashba-Dresselhaus interaction (2018)
  • Author(s): S. Katsumoto, Y. Hashimoto, X. Yao, Y. Iwasaki, and T. Nakamura
  • Organizer: 34th International Conference on the Physics of Semiconductors
  • Int'l Joint Research
• [Presentation] Doubled conductance in quantum Hall edge transport probably on electron-hole channels generated by Andreev reflection (2018)
  • Author(s): M. Onizaki, T. Nakamura, A. Endo, Y. Hashimoto, and S. Katsumoto
  • Organizer: 34th International Conference on the Physics of Semiconductors
  • Int'l Joint Research
• [Presentation] Filling factor dependence of non-adiabatic spin transition among quantum Hall edge states (2018)
  • Author(s): T. Shimizu, Y. Hashimoto, T. Nakamura, A. Endo, and S. Katsumoto
  • Organizer: 34th International Conference on the Physics of Semiconductors
  • Int'l Joint Research
• [Presentation] The in-plane field effects for the Josephson effect in two-dimensional electron system (2018)
  • Author(s): T. Nakamura
  • Organizer: Oxide Superspin International School 2018
  • Int'l Joint Research / Invited
• [Presentation] InAs二次元電子系におけるジョセフソン効果の面内磁場依存性 (2018)
  • Author(s): 中村壮智, 橋本義昭, 勝本信吾
  • Organizer: 日本物理学会2018年秋季大会
• [Presentation] Rashba-Dresselhaus複合相互作用によるトンネル異方性磁気抵抗II (2018)
  • Author(s): 橋本義昭, 松林幸宏, 中村壮智, 勝本信吾
  • Organizer: 日本物理学会2018年秋季大会
• [Presentation] 強磁性半導体中のスピン三重項超伝導 (2018)
  • Author(s): 中村壮智
  • Organizer: メゾスコピック系における非平衡スピン輸送の微視的理解とその制御
  • Invited
• [Presentation] Superconducting Proximity Effect in Ferromagnetic Semiconductor (In,Fe)As (2017)
  • Author(s): Taketomo Nakamura, L. D. Anh, Y. Hashimoto, S. Ohya, M. Tanaka, and S. Katsumoto
  • Organizer: SpinTech IX International School and Conference
  • Int'l Joint Research
• [Presentation] Possible triplet superconductivity in Nb/(In,Fe)As/Nb junctions (2017)
  • Author(s): Taketomo Nakamura, L. D. Anh, Y. Hashimoto, S. Ohya, M. Tanaka, and S. Katsumoto
  • Organizer: The 22nd International Conference on Electronic Properties of Two-Dimensional Systems (EP2DS-22/MSS-18)
  • Int'l Joint Research
• [Presentation] Proximity-Induced Superconductivity in a Ferromagnetic Semiconductor (In,Fe)As (2017)
  • Author(s): Taketomo Nakamura, L. D. Anh, Y. Hashimoto, S. Ohya, M. Tanaka, and S. Katsumoto
  • Organizer: 28th International Conference on Low Temperature Physics (LT28)
  • Int'l Joint Research
• [Presentation] 強磁性半導体-超伝導体接合における超伝導現象 (2017)
  • Author(s): 中村壮智、勝本信吾
  • Organizer: CSRN-Tokyo Workshop 2017
  • Invited
• [Presentation] Finite Supercurrent in Nb/(In, Fe)As/Nb Junctions (2017)
  • Author(s): T. Nakamura, L. D. Anh, Y. Hashimoto, S. Ohya, M. Tanaka and S. Katsumoto
  • Organizer: International School and Symposium on Nanoscale Transport and phoTonics 2017 (ISNTT2017)
  • Int'l Joint Research / Invited
• [Presentation] Long range proximity effect in a ferromagnetic semiconductor (In, Fe)As (2017)
  • Author(s): Taketomo Nakamura
  • Organizer: Oxide Superspin 2017 (OSS2017)
  • Int'l Joint Research / Invited