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Tight-binding study of interface states in semiconductor heterojunctions

A. V. Kolesnikov·R. Lipperheide·U. Wille
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Abstract

Localized interface states in abrupt semiconductor heterojunctions are studied within a tight-binding model. The intention is to provide a microscopic foundation for the results of similar studies which were based upon the two-band model within the envelope function approximation. In a two-dimensional description, the tight-binding Hamiltonian is constructed such that the Dirac-like bulk spectrum of the two-band model is recovered in the continuum limit. Localized states in heterojunctions are shown to occur under conditions equivalent to those of the two-band model. In particular, shallow interface states are identified in non-inverted junctions with intersecting bulk dispersion curves. As a specific example, the GaSb-AlSb heterojunction is considered. The matching conditions of the envelope function approximation are analyzed within the tight-binding description.

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A. V. Kolesnikov, R. Lipperheide, U. Wille. 2001-03-19. Tight-binding study of interface states in semiconductor heterojunctions. https://doi.org/10.1103/physrevb.63.205322

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