Strain tuning of topological band order in cubic semiconductors...

We theoretically explore the possibility of tuning the topological order of cubic diamond/zinc-blende semi- conductors with external strain. Based on a simple tight-binding model, we analyze the evolution of the cubic semiconductor band structure under hydrostatic or biaxial lattice expansion, by which a generic guiding princi- ple is established that biaxial lattice expansion can induce a topological phase transition of small band-gap cubic semiconductors via a band inversion and symmetry breaking at Γ point. Using density functional theory cal- culations, we demonstrate that a prototype topological trivial semiconductor, InSb, is converted to a nontrivial topological semiconductor with a 2% − 3% biaxial lattice expansion.