拓扑半金属材料角分辨光电子能谱研究进展

Progress of ARPES study on topological semimetals

拓扑半金属材料是具有拓扑保护的能带交叠的一类无能隙拓扑量子材料,具备许多独特的物理性质,是目前量子材料研究的前沿领域.根据能带交叠的简并度和维度等不同信息,拓扑半金属材料可以分为拓扑狄拉克半金属、拓扑外尔半金属和拓扑节线半金属等.具有高能量、动量分辨率的角分辨光电子能谱技术(ARPES)能够解析动量空间电子结构从而直接测量拓扑半金属中的拓扑电子态,是研究拓扑半金属材料的重要实验手段.本文系统回顾了利用ARPES技术测量的不同类型的典型拓扑半金属的电子结构特别是特征拓扑电子态,从而为拓扑半金属的物理起源、物性研究以及新奇拓扑半金属的探索提供了重要信息.

Topological semimetal,known as a type of topological quantum materials without energy gap,has attracted lots of research interests due to its unique physical properties such as novel quasiparticles,giant magnetoresistance and large carrier mobility.Topological semimetal can be further classified into topological Dirac semimetal,topological Weyl semimetal,topological nodal-line semimetal and topological semimetals with"new fermions".The high-resolution angle-resolved photoemission spectroscopy(ARPES)has emerged as a powerful experimental technique to directly visualize the electronic structure and identify the characteristic topological electronic states in topological semimetals.Here we would briefly introduce the ARPES technique and review some of the recent progress of ARPES study on the electronic structures of typical topological semimetals.We would focus mostly on the physics origin and ARPES signature of topological electronic structures and hope the readers would find it interesting and useful in the understanding of this material class which both is important in physics and has promising application potentials.