Direct observation of the spin–orbit coupling effect in magnetic Weyl semimetal Co3Sn2S2
Defa Liu, Enke Liu, Qiunan Xu, Jianlei Shen, Y. W. Li, Ding Pei, Aiji Liang, Pavel Dudin, T. K. Kim, Céphise Cacho, Yuanfeng Xu, Yuting Sun, Lei Yang, Zhongkai Liu, Claudia Felser, S. Parkin, Yulin Chen
Abstract
Abstract The spin–orbit coupling (SOC) lifts the band degeneracy that plays a vital role in the search for different topological states, such as topological insulators (TIs) and topological semimetals (TSMs). In TSMs, the SOC can partially gap a degenerate nodal line, leading to the formation of Dirac/Weyl semimetals (DSMs/WSMs). However, such SOC-induced gap structure along the nodal line in TSMs has not yet been systematically investigated experimentally. Here, we report a direct observation of such gap structure in a magnetic WSM Co 3 Sn 2 S 2 using high-resolution angle-resolved photoemission spectroscopy. Our results not only reveal the existence and importance of the strong SOC effect in the formation of the WSM phase in Co 3 Sn 2 S 2 , but also provide insights for the understanding of its exotic physical properties.