摘要
Ternary transition metal chalcogenides provide a rich platform to search and study intriguing electronic properties. Using angle-resolved photoemission spectroscopy and ab initio calculation, we investigate the electronic structure of Cu_(2)TlX_(2)(X = Se, Te), ternary transition metal chalcogenides with quasi-two-dimensional crystal structure. The band dispersions near the Fermi level are mainly contributed by the Te/Se p orbitals. According to our ab-initio calculation, the electronic structure changes from a semiconductor with indirect band gap in Cu_(2)TlSe_(2) to a semimetal in Cu_(2)TlTe_(2), suggesting a band-gap tunability with the composition of Se and Te. By comparing ARPES experimental data with the calculated results, we identify strong modulation of the band structure by spin–orbit coupling in the compounds. Our results provide a ternary platform to study and engineer the electronic properties of transition metal chalcogenides related to large spin–orbit coupling.
作者
Na Qin
Xian Du
Yangyang Lv
Lu Kang
Zhongxu Yin
Jingsong Zhou
Xu Gu
Qinqin Zhang
Runzhe Xu
Wenxuan Zhao
Yidian Li
Shuhua Yao
Yanfeng Chen
Zhongkai Liu
Lexian Yang
Yulin Chen
秦娜;杜宪;吕洋洋;康璐;尹中旭;周景松;顾旭;张琴琴;许润哲;赵文轩;李义典;姚淑华;陈延峰;柳仲楷;杨乐仙;陈宇林(State Key Laboratory of Low Dimensional Quantum Physics,Department of Physics,Tsinghua University,Beijing 100084,China;National Laboratory of Solid State Microstructures,Department of Materials Science and Engineering,Nanjing University,Nanjing 210093,China;School of Physical Science and Technology,ShanghaiTech University and CAS-Shanghai Science Research Center,Shanghai 201210,China;ShanghaiTech Laboratory for Topological Physics,Shanghai 200031,China;Frontier Science Center for Quantum Information,Beijing 100084,China;Department of Physics,Clarendon Laboratory,University of Oxford,Parks Road,Oxford 0XI 3PU,UK)
基金
supported by the National Natural Science Foundation of China (Grant No. 11774190)。
