中国物理B ›› 2023, Vol. 32 ›› Issue (5): 56401-056401.doi: 10.1088/1674-1056/acbaf2

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Stability of the topological quantum critical point between multi-Weyl semimetal and band insulator

Zhao-Kun Yang(杨兆昆)1, Jing-Rong Wang(王景荣)2, and Guo-Zhu Liu(刘国柱)1,†   

  1. 1 Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China;
    2 High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei 230031, China
  • 收稿日期:2022-10-21 修回日期:2023-02-10 接受日期:2023-02-10 出版日期:2023-04-21 发布日期:2023-04-26
  • 通讯作者: Guo-Zhu Liu E-mail:gzliu@ustc.edu.cn
  • 基金资助:
    Project supported by the Natural Science Foundation of Anhui Province, China (Grant No. 2208085MA11) and the National Natural Science Foundation of China (Grants Nos. 11974356, 12274414, and U1832209).

Stability of the topological quantum critical point between multi-Weyl semimetal and band insulator

Zhao-Kun Yang(杨兆昆)1, Jing-Rong Wang(王景荣)2, and Guo-Zhu Liu(刘国柱)1,†   

  1. 1 Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China;
    2 High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei 230031, China
  • Received:2022-10-21 Revised:2023-02-10 Accepted:2023-02-10 Online:2023-04-21 Published:2023-04-26
  • Contact: Guo-Zhu Liu E-mail:gzliu@ustc.edu.cn
  • Supported by:
    Project supported by the Natural Science Foundation of Anhui Province, China (Grant No. 2208085MA11) and the National Natural Science Foundation of China (Grants Nos. 11974356, 12274414, and U1832209).

摘要: One could tune a topological double-Weyl semimetal or a topological triple-Weyl semimetal to become a topologically trivial insulator by opening a band gap. This kind of quantum phase transition is characterized by the change of certain topological invariant. A new gapless semimetallic state emerges at each topological quantum critical point. Here we perform a renormalization group analysis to investigate the stability of such critical points against perturbations induced by random scalar potential and random vector potential. We find that the quantum critical point between double-Weyl semimetal and band insulator is unstable and can be easily turned into a compressible diffusive metal by any type of weak disorder. The quantum critical point between triple-Weyl semimetal and band insulator flows to a stable strong-coupling fixed point if the system contains a random vector potential merely along the z-axis, but becomes a compressible diffusive metal when other types of disorders exist.

关键词: topological quantum critical points, Weyl semimetal, disorder, renormalization group

Abstract: One could tune a topological double-Weyl semimetal or a topological triple-Weyl semimetal to become a topologically trivial insulator by opening a band gap. This kind of quantum phase transition is characterized by the change of certain topological invariant. A new gapless semimetallic state emerges at each topological quantum critical point. Here we perform a renormalization group analysis to investigate the stability of such critical points against perturbations induced by random scalar potential and random vector potential. We find that the quantum critical point between double-Weyl semimetal and band insulator is unstable and can be easily turned into a compressible diffusive metal by any type of weak disorder. The quantum critical point between triple-Weyl semimetal and band insulator flows to a stable strong-coupling fixed point if the system contains a random vector potential merely along the z-axis, but becomes a compressible diffusive metal when other types of disorders exist.

Key words: topological quantum critical points, Weyl semimetal, disorder, renormalization group

中图分类号:  (Dynamic critical phenomena)

  • 64.60.Ht
64.60.ae (Renormalization-group theory) 64.70.Tg (Quantum phase transitions)