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Electronic structure and band gap composition-dependence of the II-VI quaternary alloys

A. E. Garcia·A. Zepeda-Navratil·A. Camacho·D. Olguin·R. Baquero
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Abstract

Based on a successful description of II-VI ternary alloys, which introduces an empirical bowing parameter to the widely used virtual crystal approximation, we set up a tight-binding Hamiltonian to describe the Zn_{1-y}Cd_ySe_{1-x}Te_x and Zn_{.9}Cd_{.1}S_{.07}Se_{.93} quaternary alloys. We just use a formula that can be thought as a straightforward generalization of the virtual crystal approximation for this case. Our Hamiltonians reproduce very well the change in the band gap value with the composition observed in recent experimental reports.

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A. E. Garcia, A. Zepeda-Navratil, A. Camacho, D. Olguin, R. Baquero. 1996-12-05. Electronic structure and band gap composition-dependence of the II-VI quaternary alloys. https://arxiv.org/abs/cond-mat/9612051

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