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arXiv · 1307.5985

Impact of cation-based localized electronic states on the conduction and valence band structure of AlInN alloys

S. Schulz·M. A. Caro·E. P. O'Reilly
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Abstract

We demonstrate that cation-related localized states strongly perturb the band structure of $\text{Al}_{1-x}\text{In}_x$N leading to a strong band gap bowing at low In content. Our first-principles calculations show that In-related localized states are formed both in the conduction and the valence band in $\text{Al}_{1-x}\text{In}_x$N for low In composition, $x$, and that these localized states dominate the evolution of the band structure with increasing $x$. Therefore, the commonly used assumption of a single composition-independent bowing parameter breaks down when describing the evolution both of the conduction and of the valence band edge in $\text{Al}_{1-x}\text{In}_x$N.

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S. Schulz, M. A. Caro, E. P. O'Reilly. 2014-04-28. Impact of cation-based localized electronic states on the conduction and valence band structure of AlInN alloys. https://doi.org/10.1063/1.4872317

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