Electronic structure of (InSb)m/(HgTe)n short period superlattices

Abstract

The electronic structure of (InSb)m/(HgTe)n short period superlattices grown along the (001) direction is studied theoretically using norm-conserving pseudo-potentials together with the local-density approximation for the exchange-correlation potential. The band structure depends on the value of m and n, the number of mono-layers and on the ordering of atoms at the InSb/HgTe interface in one unit cell. Our calculation indicates that the superlattice can be a semiconductor having a band gap between the occupied and unoccupied bands, or a metal with no band gap at the Fermi energy. According to the further calculation of total charge density between (InSb)m/(HgTe)n with different structures, a clearly different behavior happens when the structure changes from a system with a gap and a system without a gap.