Emergence of Weyl Fermions by Ferrimagnetism in a Noncentrosymmetric Magnetic Weyl Semimetal

ORAL

Abstract

Searching for angle-resolved photoemission spectroscopy (ARPES) signatures across magnetic phase transition is typically a difficult task, partly due to the formation of magnetic domains that are smaller than the typical beam spot size. In relation to the magnetic Weyl semimetal, many attempts have been made to study the shift of Weyl nodes across the magnetic transition. However, this is intrinsically difficult due to the smallness of the Zeeman energy. We have come up with a novel attempt, that is to look for evidence of Brillouin zone folding in a ferrimagnet. Here, using ARPES, we provide a new example of this by visualizing the electronic structure of a noncentrosymmetric magnetic Weyl semimetal candidate NdAlSi in both the paramagnetic and ferrimagnetic states. We observe surface Fermi arcs and bulk Weyl fermion dispersion as well as the regulation of Weyl fermions by ferrimagnetism. Our results establish NdAlSi as a magnetic Weyl semimetal and provide the first experimental observation of ferrimagnetic regulation of Weyl fermions in condensed matter.

*The work presented here was financially supported by the Swedish Research council (2019-00701) and the Knut and Alice Wallenberg foundation (2018.0104).

Publication: C. Li et al. Arxiv: 2303.17302

Presenters

  • Cong Li

    • Royal Institute of Technology
    • KTH
    • KTH Royal Institute of Technology

Authors

  • Cong Li

    • Royal Institute of Technology
    • KTH
    • KTH Royal Institute of Technology

  • Jianfeng Zhang

    • Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China

  • Yang Wang

    • Royal Institute of Technology

  • Hongxiong Liu

    • Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China

  • Qinda Guo

    • Royal Institute of Technology
    • KTH Royal Institute of Technology

  • Emile Rienks

    • Helmholtz-Zentrum Berlin f¨ur Materialien und Energie, Elektronenspeicherring BESSY II, Albert-Einstein-Straße 15, 12489 Berlin, Germany
    • HZB

  • Wanyu Chen

    • Royal Institute of Technology

  • François Bertran

    • Synchrotron SOLEIL, L'Orme des Merisiers, D´epartementale 128, 91190 Saint-Aubin, France
    • Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, Gif-sur-Yvette

  • Huancheng Yang

    • Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials & Micro-nano Devices, Renmin University of China, Beijing 100872, China

  • Dibya Phuyal

    • Royal Institute of Technology

  • Hanna Fedderwitz

    • MAX IV Laboratory, Lund University, 22100 Lund, Sweden

  • Balasubramanian Thiagarajan

    • MAX IV Laboratory, Lund University, 22100 Lund, Sweden

  • Maciej Dendzik

    • Royal Institute of Technology

  • Mgnus H. Berntsen

    • Royal Institute of Technology

  • Youguo Shi

    • Chinese Academy of Sciences
    • Institute of Physics, Chinese Academy of Sciences
    • Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China

  • Tao Xiang

    • Chinese Academy of Sciences

  • Oscar Tjernberg

    • Royal Institute of Technology
    • KTH
    • KTH Royal Institute of Technology