HOLE SUBBANDS AND EFFECTIVE MASSES IN P-DOPED [113]-GROWN HETEROJUNCTIONS

We calculate the hole band structure and effective masses in a two-dimensional hole gas (2DHG) in p-doped [113]-grown heterojunctions. A Hamiltonian for the 2DHG is derived which is formally similar to the Luttinger Hamiltonian which describes the hole gas in conventional [001] heterojunctions. We use a limited analytical basis set of uncoupled heavy-hole and light-hole states which allow us to obtain a qualitative description of the differences between [113]- and [001]-grown heterojunctions. We avoid the self-consistent calculation of the electrostatic confining potential by use of an analytical model which proved to be very accurate. In addition to numerical calculations, we derive analytical expressions of the hole subbands which are valid at small in-plane wave vectors. We compute the classical effective masses of the 2DHG as a function of the charge density and we compare with those obtained for conventional [001]-grown structures. We found that the latter are systematically larger in a broad range of carrier concentrations. © 1995 The American Physical Society.