Amplification of Acoustic Wave in GaN in the Presence of Slowly Changing Periodic Electric Field

TL;DR

This paper investigates how slowly changing periodic electric fields influence acoustic wave amplification in GaN, deriving analytical expressions and identifying resonant frequencies that could enable maser applications.

Contribution

It provides an analytical model for acoustoelectric amplification in GaN under combined electric fields and identifies conditions for resonant amplification peaks.

Findings

Acoustoelectric gain peaks at specific frequencies with increasing electric field.

A second resonant peak appears at higher electric field levels.

Potential use of GaN as a maser based on amplification properties.

Abstract

Acoustic wave propagation in bulk GaN Semiconductor in the presence of a slowly changing a.c electric field and a constant electric field has been studied. Analytical expression for the attenuation (amplification) coefficient has been obtained. It is shown that the a.c electric field is acting as a modulator and that the acoustoelectric gain increases to a maximum value and then fall off as the acoustic wave frequency is increased. Also for a a.c electric field of 4 x 104 V/CM the acoustoelectric gain remains zero until the acoustic wave frequency is about 5.8x1012Hz then a resonant amplification peak appears. If the a.c electric field is increased a second resonant peak accurs at 8.7x1012Hz. It is therefore suggested that the sample can be used as a maser.