Tight binding modelling of electronic structure of GaPN/GaP, InAsN/InAs and GaAsN/GaAs heterostructures

Abstract

We present a second nearest neighbor semi‐empirical sp3s* tight binding model to calculate the electronic band structure of nitride/arsenide or phosphide heterostructures. The sp3s* model Hamiltonian includes the spin‐orbit coupling of p‐states, second nearest neighbor (2NN) atomic interactions. Atomic energy levels and bond lengths of ternary semi‐ conductors are taken as nonlinear function of alloy com‐ position. The model findings for InAsN/InAs, GaPN/GaP and GaAsN/GaAs structures are in excellent agreement with experiment for the band gaps at Γ, L and X symmetry points. It is found that the bulk band structure properties and lattice mismatch strain have significant effects on band offsets and GaPN/GaP, InAsN/InAs and GaAsN/GaAs heterostructures are type II for small composition (0.0 < x < 0.50) and become type I for large composition 0.50 < x < 1.0. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Tight binding modeling of electronic properties of III‐V based heterostructures

“…where first two terms are the undistorted part of the bond length, the last one is the distorted part of the bond length due to cation-anion relaxation in the − A B C ternary as Figure 1 Electronic band structure and density of states of GaAs calculated by using sp3s* 2NN (dashed) [20,21] and sp3d5s* (solid) [2] TB methods.…”

“…Tight binding parameterization of the matrix elements for sp3s* 2NN interaction have been done as explained in our previous work [20]. Jancu et al [2,17] parameters are used to get sp3d5s* tight binding dispersion curves.…”