中国物理B ›› 2026, Vol. 35 ›› Issue (3): 37801-037801.doi: 10.1088/1674-1056/ae2abc

• • 上一篇    

Electrodynamics of a prototypical altermagnetic compound MnTe

Bixia Gao(高碧霞)1,2, Yixuan Luo(罗伊轩)3, Liye Cao(曹立叶)1,2, Tao Sun(孙涛)4, Zehao Yu(于泽浩)1,2, Lei Wang(王蕾)1,2, Xinyu Zhang(张新雨)1,2, Hongbo Hu(胡宏波)1,2, Yanfeng Guo(郭艳峰)3,5, and Rongyan Chen(陈荣艳)1,2,†   

  1. 1 Center for Advanced Quantum Studies, School of Physics and Astronomy, Beijing Normal University, Beijing 100875, China;
    2 Key Laboratory of Multiscale Spin Physics, Ministry of Education, Beijing Normal University, Beijing 100875, China;
    3 State Key Laboratory of Quantum Functional Materials, School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China;
    4 Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
    5 ShanghaiTech Laboratory for Topological Physics, ShanghaiTech University, Shanghai 201210, China
  • 收稿日期:2025-09-01 修回日期:2025-12-05 接受日期:2025-12-10 发布日期:2026-02-11
  • 基金资助:
    R.Y.C. acknowledges the support by the National Key Research and Development Program of China (Grant Nos. 2021YFA1400400 and 2023YFA1406100), the National Natural Science Foundation of China (Grant No. 12074042), the Young Scientists Fund of the National Natural Science Foundation of China (Grant No. 11704033), and the Fundamental Research Funds for the Central Universities (Grant No. 2243300003). Y.F.G. acknowledges the open research fund of Beijing National Laboratory for Condensed Matter Physics (Grant No. 2023BNLCMPKF002). This work was supported by the Synergetic Extreme Condition User Facility (SECUF).

Electrodynamics of a prototypical altermagnetic compound MnTe

Bixia Gao(高碧霞)1,2, Yixuan Luo(罗伊轩)3, Liye Cao(曹立叶)1,2, Tao Sun(孙涛)4, Zehao Yu(于泽浩)1,2, Lei Wang(王蕾)1,2, Xinyu Zhang(张新雨)1,2, Hongbo Hu(胡宏波)1,2, Yanfeng Guo(郭艳峰)3,5, and Rongyan Chen(陈荣艳)1,2,†   

  1. 1 Center for Advanced Quantum Studies, School of Physics and Astronomy, Beijing Normal University, Beijing 100875, China;
    2 Key Laboratory of Multiscale Spin Physics, Ministry of Education, Beijing Normal University, Beijing 100875, China;
    3 State Key Laboratory of Quantum Functional Materials, School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China;
    4 Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
    5 ShanghaiTech Laboratory for Topological Physics, ShanghaiTech University, Shanghai 201210, China
  • Received:2025-09-01 Revised:2025-12-05 Accepted:2025-12-10 Published:2026-02-11
  • Contact: Rongyan Chen E-mail:rychen@bnu.edu.cn
  • Supported by:
    R.Y.C. acknowledges the support by the National Key Research and Development Program of China (Grant Nos. 2021YFA1400400 and 2023YFA1406100), the National Natural Science Foundation of China (Grant No. 12074042), the Young Scientists Fund of the National Natural Science Foundation of China (Grant No. 11704033), and the Fundamental Research Funds for the Central Universities (Grant No. 2243300003). Y.F.G. acknowledges the open research fund of Beijing National Laboratory for Condensed Matter Physics (Grant No. 2023BNLCMPKF002). This work was supported by the Synergetic Extreme Condition User Facility (SECUF).

摘要: Altermagnetism, characterized by compensated antiparallel spins and momentum-dependent spin splitting, has offered a promising platform for novel spintronic phenomena. Among this class of materials, hexagonal MnTe stands out due to its high Néel temperature and giant spin splitting. However, a comprehensive understanding of its charge dynamics remains incomplete. Here, we employ infrared spectroscopy to investigate the charge dynamics of single crystalline MnTe. The low energy optical conductivity reveals a suppressed Drude response across all temperatures, consistent with the reported p-type doping as indicated by previous angle-resolved photoemission spectroscopy (ARPES) measurement. An indirect band gap of about 0.48 eV attributed to impurity-assisted transitions, and a direct gap of 1.60 eV are identified via the Tauc relation at 10 K. Moreover, we observe a subtle difference at around 1.44 eV in the optical conductivity between the antiferromagnetic and paramagnetic states, which might be linked to altermagnetism-related band splitting. Additionally, Fano line shape analysis of a phonon mode at around 135 cm$^{-1}$ reveals appreciable coupling between the phonon and spin fluctuations near the Néel temperature. Our results provide key insights into the charge dynamics of MnTe, underscoring its rich physics beyond a conventional semiconductor.

关键词: altermagnetism, MnTe, infrared spectroscopy

Abstract: Altermagnetism, characterized by compensated antiparallel spins and momentum-dependent spin splitting, has offered a promising platform for novel spintronic phenomena. Among this class of materials, hexagonal MnTe stands out due to its high Néel temperature and giant spin splitting. However, a comprehensive understanding of its charge dynamics remains incomplete. Here, we employ infrared spectroscopy to investigate the charge dynamics of single crystalline MnTe. The low energy optical conductivity reveals a suppressed Drude response across all temperatures, consistent with the reported p-type doping as indicated by previous angle-resolved photoemission spectroscopy (ARPES) measurement. An indirect band gap of about 0.48 eV attributed to impurity-assisted transitions, and a direct gap of 1.60 eV are identified via the Tauc relation at 10 K. Moreover, we observe a subtle difference at around 1.44 eV in the optical conductivity between the antiferromagnetic and paramagnetic states, which might be linked to altermagnetism-related band splitting. Additionally, Fano line shape analysis of a phonon mode at around 135 cm$^{-1}$ reveals appreciable coupling between the phonon and spin fluctuations near the Néel temperature. Our results provide key insights into the charge dynamics of MnTe, underscoring its rich physics beyond a conventional semiconductor.

Key words: altermagnetism, MnTe, infrared spectroscopy

中图分类号:  (Infrared and Raman spectra)

  • 78.30.-j
78.40.Fy (Semiconductors) 63.20.-e (Phonons in crystal lattices) 75.50.Ee (Antiferromagnetics)