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arXiv · 2105.00444

Electronic Structure Examination on the Topological Properties of CaMnSb$_{2}$ by Angle-Resolved Photoemission Spectroscopy

Abstract

We have carried out detailed high resolution ARPES measurements and band structure calculations to study the electronic structure of CaMnSb$_{2}$. The observed Fermi surface mainly consists of one hole pocket around ${\Gamma}$ point and one tiny hole pocket at Y point. Strong spectral weight accumulation along the ${\Gamma}$-X direction is observed on the hole-like Fermi surface around ${\Gamma}$ point, suggesting strong anisotropy of the density of states along the Fermi surface. The tiny hole pocket at Y point originates from an anisotropic Dirac-like band with the crossing point of the linear bands lying $\sim$ 10 meV above the Fermi level. These observations are in a good agreement with the band structure calculations. In addition, we observe additional features along the ${\Gamma}$-Y line that cannot be accounted for by the band structure calculations. Our results provide important information in understanding and exploration of novel properties in CaMnSb$_{2}$ and related materials.

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Hongtao Rong, Liqin Zhou, Junbao He, Chunyao Song, Jianwei Huang, Cheng Hu, Yu Xu, Yongqing Cai, Hao Chen, Cong Li, Qingyan Wang, Lin Zhao, Zhihai Zhu, Guodong Liu, Zuyan Xu, Genfu Chen, Hongming Weng, X. J. Zhou. 2021-05-02. Electronic Structure Examination on the Topological Properties of CaMnSb$_{2}$ by Angle-Resolved Photoemission Spectroscopy. https://doi.org/10.1103/physrevb.103.245104

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