Strain-induced topological phase transition with inversion of the in-plane electric polarization in tiny-gap semiconductor SiGe monolayer

摘要

SiGe monolayer. ( ) Geometric structure. Red and green balls correspond to germanium and silicon, respectively. ( ) Total energy with respect to the equilibrium value as a function of the biaxial strain . ( ) Band gap as a function of . Black and red symbols correspond to the band gap without and with spin–orbit coupling, respectively.