Topological Electronic States on the Surface of a Strained Gapless Semiconductor

Abstract We develop the theory describing the topological electronic states on the surface of a gapless strained semiconductor arisen from the mixing of conduction and valence bands. It follows from the present theory that the strain-induced band gap in the Brillouin zone center of the semiconductor results in the surface electronic states with the Dirac linear dispersion characteristic for topologically protected states. The structure of these surface electronic states is studied analytically near their Dirac point within the formalism based on the Luttinger Hamiltonian. The results bring attention to the rich surface physics relevant for topological systems.