中国物理B ›› 2026, Vol. 35 ›› Issue (2): 27101-027101.doi: 10.1088/1674-1056/ae1c27

• • 上一篇    

Charge-transfer-induced re-entrant ferromagnetism in twisted-bilayer-MoTe2/hBN/WSe2

Shaozheng Wang(王绍政)1,†, Xumin Chang(常旭敏)1,†, Feng Liu(刘峰)1, Yuchen Zheng(郑宇辰)3, Juncai Wu(吴俊才)3, Tong Zheng(郑桐)3, Kenji Watanabe4, Takashi Taniguchi4, and Shengwei Jiang(姜生伟)1,2,5,‡   

  1. 1 State Key Laboratory of Micro-nano Engineering Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China;
    2 Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China;
    3 Zhiyuan College, Shanghai Jiao Tong University, Shanghai 200240, China;
    4 National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan;
    5 Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai 201210, China
  • 收稿日期:2025-09-17 修回日期:2025-10-29 接受日期:2025-11-06 发布日期:2026-01-21
  • 通讯作者: Shengwei Jiang E-mail:swjiang@sjtu.edu.cn
  • 基金资助:
    We thank Prof. Yang Zhang for fruitful discussions. This work was supported by the National Key R&D Program of China (Grant Nos. 2021YFA1400100 and 2021YFA1401400), the National Natural Science Foundation of China (Grant Nos. 12550403, 12174250 and 12141404), and the Shanghai Jiao Tong University 2030 Initiative Program B (Grant No. WH510207202). K.W. and T.T. acknowledge support from JSPS KAKENHI (Grant Nos. 21H05233 and 23H02052) and the World Premier International Research Center Initiative (WPI), MEXT, Japan. Device fabrication was supported by the Micro-Nano Fabrication Platform of the School of Physics and Astronomy at Shanghai Jiao Tong University.

Charge-transfer-induced re-entrant ferromagnetism in twisted-bilayer-MoTe2/hBN/WSe2

Shaozheng Wang(王绍政)1,†, Xumin Chang(常旭敏)1,†, Feng Liu(刘峰)1, Yuchen Zheng(郑宇辰)3, Juncai Wu(吴俊才)3, Tong Zheng(郑桐)3, Kenji Watanabe4, Takashi Taniguchi4, and Shengwei Jiang(姜生伟)1,2,5,‡   

  1. 1 State Key Laboratory of Micro-nano Engineering Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China;
    2 Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China;
    3 Zhiyuan College, Shanghai Jiao Tong University, Shanghai 200240, China;
    4 National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan;
    5 Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai 201210, China
  • Received:2025-09-17 Revised:2025-10-29 Accepted:2025-11-06 Published:2026-01-21
  • Contact: Shengwei Jiang E-mail:swjiang@sjtu.edu.cn
  • Supported by:
    We thank Prof. Yang Zhang for fruitful discussions. This work was supported by the National Key R&D Program of China (Grant Nos. 2021YFA1400100 and 2021YFA1401400), the National Natural Science Foundation of China (Grant Nos. 12550403, 12174250 and 12141404), and the Shanghai Jiao Tong University 2030 Initiative Program B (Grant No. WH510207202). K.W. and T.T. acknowledge support from JSPS KAKENHI (Grant Nos. 21H05233 and 23H02052) and the World Premier International Research Center Initiative (WPI), MEXT, Japan. Device fabrication was supported by the Micro-Nano Fabrication Platform of the School of Physics and Astronomy at Shanghai Jiao Tong University.

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摘要： Ferromagnetism in moiré flat-band systems has been extensively studied in the first valence miniband of twisted MoTe$_2$, while its controlled realization at higher moiré fillings remains largely unexplored, except for very recent works reporting correlated magnetism near half filling of the second moiré band. Here, we investigate rhombohedral-stacked twisted MoTe$_2$/hBN/WSe$_2$ heterostructures and uncover two distinct ferromagnetic (FM) regions: one centered near ${v}_{\rm h} \approx 3$ (half filling of the second moiré valence miniband) at zero displacement field, and a re-entrant FM phase that emerges for ${v}_{\rm h} > 3$ only under a finite out-of-plane electric field. These FM regions are separated by a narrow filling window with a strongly suppressed magnetic circular dichroism (MCD) response. Layer-sensitive exciton spectroscopy identifies that WSe$_2$ is hole-doped in the re-entrant FM region, consistent with partial charge transfer from MoTe$_2$ to WSe$_2$. We propose that electric-field-induced layer repopulation stabilizes the re-entrant ferromagnetic phase by pinning the effective MoTe$_2$ filling near ${v}_{\rm h} \approx 3$ while adding carriers to the remote WSe$_2$ layer. Our results demonstrate that remote-layer population control is an effective tuning knob for magnetic ordering in higher moiré minibands, extending the design space for correlated spin-valley phases in transition metal dichalcogenide heterostructures.

关键词: moiré superlattice, ferromagnetism, magneto-optical spectroscopy

Abstract: Ferromagnetism in moiré flat-band systems has been extensively studied in the first valence miniband of twisted MoTe$_2$, while its controlled realization at higher moiré fillings remains largely unexplored, except for very recent works reporting correlated magnetism near half filling of the second moiré band. Here, we investigate rhombohedral-stacked twisted MoTe$_2$/hBN/WSe$_2$ heterostructures and uncover two distinct ferromagnetic (FM) regions: one centered near ${v}_{\rm h} \approx 3$ (half filling of the second moiré valence miniband) at zero displacement field, and a re-entrant FM phase that emerges for ${v}_{\rm h} > 3$ only under a finite out-of-plane electric field. These FM regions are separated by a narrow filling window with a strongly suppressed magnetic circular dichroism (MCD) response. Layer-sensitive exciton spectroscopy identifies that WSe$_2$ is hole-doped in the re-entrant FM region, consistent with partial charge transfer from MoTe$_2$ to WSe$_2$. We propose that electric-field-induced layer repopulation stabilizes the re-entrant ferromagnetic phase by pinning the effective MoTe$_2$ filling near ${v}_{\rm h} \approx 3$ while adding carriers to the remote WSe$_2$ layer. Our results demonstrate that remote-layer population control is an effective tuning knob for magnetic ordering in higher moiré minibands, extending the design space for correlated spin-valley phases in transition metal dichalcogenide heterostructures.

Key words: moiré superlattice, ferromagnetism, magneto-optical spectroscopy

中图分类号:  (Excitons and related phenomena)

  • 71.35.-y
75.70.Tj (Spin-orbit effects) 78.20.Ls (Magneto-optical effects)