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