Electronic structure examination of the topological properties of CaMnSb2 by angle-resolved photoemission spectroscopy

We have carried out detailed high-resolution angle-resolved photoemission spectroscopy measurements and band structure calculations to study the electronic structure of CaMnSb2. The observed Fermi surface mainly consists of one hole pocket around the Gamma point and one tiny hole pocket at the Y point. Strong spectral weight accumulation along the Gamma-X direction is observed on the holelike Fermi surface around the Gamma point, suggesting strong anisotropy of the density of states along the Fermi surface. The tiny hole pocket at the Y point originates from an anisotropic Dirac-like band with the crossing point of the linear bands lying similar to 10 meV above the Fermi level. These observations are in 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 the understanding and exploration of novel properties in CaMnSb2 and related materials.