A planar force-constant model for phonons in wurtzite GaN and AlN: Application to hexagonal GaN/AlN superlattices

TL;DR

This paper develops a planar force-constant model for longitudinal phonons in wurtzite GaN and AlN, and applies it to analyze phonon modes and confinement effects in hexagonal GaN/AlN superlattices.

Contribution

A new planar force-constant model specifically for longitudinal phonons in wurtzite GaN and AlN, applied to superlattice phonon mode analysis.

Findings

Phonon confinement in GaN/AlN superlattices is characterized.

The model accurately describes phonon behavior along the [0001] direction.

Insights into superlattice phonon mode localization are provided.

Abstract

A planar force-constant model is developed for longitudinal phonons of wurtzite GaN and AlN propagating along the [0001] direction. The proposed model is then applied to the study of the phonon modes in hexagonal GaN/AlN superlattices in the longitudinal polarization. The confinement of the superlattice phonon mode is discussed.