Two-dimensional Dirac dispersion in the layered compound BaCdSb2

We report a comprehensive study of the electronic structure of layered compound BaCdSb2 by using electrical transport measurements, first-principles calculations, and angle-resolved photoemission spectroscopy (ARPES). The samples show semiconductorlike temperature dependence of resistivity and low carrier density. The Shubnikov-de Haas (SdH) oscillations with a single frequency reveal a small two-dimensional (2D) cylinderlike Fermi surface (FS), a light cyclotron effective mass, and trivial Berry's phase. Quantum limit can be achieved under a moderate magnetic field. The calculated bands without any renormalization are well consistent with the ARPES results, showing the Dirac band crossing with 2D character near the Fermi energy and a gap of about 34 meV at the Dirac point induced by spin-orbit interaction. The SdH oscillations can be identified to the Dirac band by the similar cross sectional areas of FSs. Our findings indicate BaCdSb2 is a promising material for researching the quantum phenomena of the 2D Dirac fermions.

Automated summary

In this study, the electronic structure of the layered compound BaCdSb2 was investigated using various methods, revealing its potential for researching quantum phenomena of 2D Dirac fermions. The samples exhibit semiconductor-like behavior with low carrier density and a small 2D Fermi surface, indicating promise for future research into quantum effects. The results also demonstrate consistent agreement between calculated band structures and experimental data, highlighting the unique properties of BaCdSb2 as a material for studying quantum phenomena.