Electronic structure and topological transition of SnTe at high pressure

Recent x-ray diffraction measurements and first-principles calculations have revealed intriguing structural evolution of tin telluride (SnTe) under high pressure. Here we report on a systematic study of the electronic band structure, density of states, Fermi surface and charge density of SnTe at high pressure using first-principles density functional theory calculations. Our results unveil an electronic topological transition in the cubic Fm-3m phase of SnTe with its Fermi surface changing from disconnected pockets to inter-connected quasicubic tubes near the L points of the Brillouin zone under high pressure. The pressure-induced quasicubic tubular Fermi surface is similar to that previously obtained via carrier doping. The induced change in electronic charge distribution stabilizes the Fm-3m structure and thus suppresses the transition to the rhombohedral structure, which explains experimental observations. Furthermore, our calculations show that pressure-induced electronic topological transition is also present in the orthorhombic Cmcm and Pnma phases of SnTe in the pressure range of 5 to 18 GPa, but this transition is absent in the high-pressure (above 18 GPa) Pm-3m phase.