Author:
Ma 马 Huan 欢,Tan 谭 Ning 宁,Wu 吴 Xuchuan 徐传,Li 李 Man 满,Wang 王 Yiyan 义炎,Lu 路 Hongyan 洪艳,Xia 夏 Tianlong 天龙,Wang 王 Shancai 善才
Abstract
We investigate the electronic structure of NbGeSb with non-symmorphic symmetry. We employ angle-resolved photoemission spectroscopy (ARPES) to observe and identify the bulk and surface states over the Brillouin zone. By utilizing high-energy photons, we identify the bulk Fermi surface and bulk nodal line along the direction X–R, while the Fermi surface of the surface state is observed by using low-energy photons. We observe the splitting of surface bands away from the high-symmetry point
X
¯
. The density functional theory calculations on bulk and 1 to 5-layer slab models, as well as spin textures of NbGeSb, verify that the band splitting could be attributed to the Rashba-like spin–orbit coupling caused by space-inversion-symmetry breaking at the surface. These splitted surface bands cross with each other, forming two-dimensional Weyl-like crossings that are protected by mirror symmetry. Our findings provide insights into the two-dimensional topological and symmetry-protected band inversion of surface states.
Subject
General Physics and Astronomy