Electronic structure of wurtzite and zinc-blende AlN

TL;DR

This study combines experimental x-ray emission spectroscopy and theoretical density functional theory calculations to analyze and compare the electronic structures of AlN in wurtzite and zinc-blende phases, revealing good overall agreement and minor phase differences.

Contribution

It provides a comprehensive comparison of experimental and theoretical electronic structures of AlN in two phases, highlighting phase similarities and differences with detailed spectral analysis.

Findings

Good agreement between experimental spectra and theoretical DOS

Large hybridization of valence states observed

Minor differences between wurtzite and zinc-blende phases

Abstract

The electronic structure of AlN in wurtzite and zinc-blende phases is studied experimentally and theoretically. By using x-ray emission spectroscopy, the Al 3p, Al 3s and N 2p spectral densities are obtained. The corresponding local and partial theoretical densities of states (DOS), as well as the total DOS and the band structure, are calculated by using the full potential linearized augmented plane wave method, within the framework of the density functional theory. There is a relatively good agreement between the experimental spectra and the theoretical DOS, showing a large hybridization of the valence states all along the valence band. The discrepancies between the experimental and theoretical DOS, appearing towards the high binding energies, are ascribed to an underestimation of the valence band width in the calculations. Differences between the wurtzite and zinc-blende phases are small and reflect the slight variations between the atomic arrangements of both phases.