Electronic structure of the valence band of the II--VI wide band gap binary/ternary alloy interfaces

TL;DR

This paper investigates the electronic structure of valence bands at II--VI alloy interfaces using tight-binding and Green's function methods, revealing interface states consistent with experimental and theoretical findings.

Contribution

It introduces a detailed calculation of valence band structures at alloy interfaces, including ternary alloys, using empirically fitted Hamiltonians and Green's function matching.

Findings

Identification of non-dispersive interface states at alloy interfaces

Comparison of results with existing theoretical calculations for (001) surfaces

Validation of Hamiltonians for describing band gap changes with composition

Abstract

We present an electronic structure calculation of the valence band for some II--VI binary/ternary alloy interfaces. We use the empirical tight-binding method and the surface Green's function matching method. For the ternary alloys we use our previously set Hamiltonians they describe well the band gap change with composition obtained experimentally. At the interface domain, we find three non-dispersive and two interface states besides the known bulk bands. The non-dispersive states are reminiscent of the ones already obtained experimentally as well as theoretically, in (001)-oriented surfaces. We make use of the available theoretical calculations for the (001)-oriented surfaces of the binary compounds and for the binary/binary interfaces to compare our new results with.