Virtual crystal description of III-V semiconductor alloys in the tight binding approach

M. O. Nestoklon; R. Benchamekh; P. Voisin

doi:10.1088/0953-8984/28/30/305801

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arXiv · 1603.03227

Virtual crystal description of III-V semiconductor alloys in the tight binding approach

M. O. Nestoklon·R. Benchamekh·P. Voisin

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Abstract

We propose a simple and effective approach to construct the empirical tight-binding parameters of ternary alloys in the virtual crystal approximation. This combines a new, compact formulation of the strain parameters and a linear interpolation of the hamiltonians of binary materials strained to the alloy equilibrium lattice parameter. We show that it is possible to obtain a perfect description of the bandgap bowing of ternary alloys in the InGaAsSb family of materials. Furthermore, this approach is in a good agreement with supercell calculations using the same set of parameters. This scheme opens a way for atomistic modeling of alloy-based opto-electronic devices without extensive supercell calculations.

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M. O. Nestoklon, R. Benchamekh, P. Voisin. 2016-03-10. Virtual crystal description of III-V semiconductor alloys in the tight binding approach. https://doi.org/10.1088/0953-8984/28/30/305801

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