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

作　　者：杨兆昆 王景荣 刘国柱 Zhao-Kun Yang;Jing-Rong Wang;Guo-Zhu Liu(Department of Modern Physics,University of Science and Technology of China,Hefei 230026,China;High Magnetic Field Laboratory of Anhui Province,Chinese Academy of Sciences,Hefei 230031,China)

机构地区：[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

出　　处：《Chinese Physics B》2023年第5期131-140,共10页中国物理B（英文版）

基　　金：the Natural Science Foundation of Anhui Province,China(Grant No.2208085MA11);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 

分 类 号：O469[理学—凝聚态物理] TB30[理学—电子物理学]