Merging thermoelectrics, topological order, and superconductivity in a single compound
일 시 : 2020년 11월 27일 금요일 11:30
연 사 : Xiaojia Chen
소 속 : Center for High Pressure Science & Technology Advanced Research, China
장 소 : 온라인 진행 ( https://us02web.zoom.us/j/84281887278 , 줌회의 ID: 842 8188 7278 )
초 록
Topological insulating state as a novel quantum state holds a promise for future device development in quantum computation. Thermoelectrics and superconductivity are important for energy development and revolution. By choosing a highly efficient thermoelectric material PbSe, we show that the significant enhancement of the figure of merit can be realized through pressure-driven electronic topological transition. The record high figure of merit of 1.7 at room temperature in this material suggests the potential technical applications. After passing the electronic topological transition, we provide experimental evidence to support the band inversion and the entrance of the deserved topological crystalline insulating state. Upon heavy compression, we detect superconductivity over a wide pressure regime. The emergence of superconductivity is found to be the result of the suppression of the lattice modulation. We thus obtain tunable thermoelectric performance, topological order, and superconductivity in a single compound. These results point to the powerful role of pressure played in tuning these important quantum effects.