Observation of lattice waves through observation of the photoluminescence Blinking in InGaN Quantum Well devices

TL;DR

This paper links photoluminescence blinking in InGaN quantum wells to lattice wave interference caused by thermal vibrations, providing experimental observations of these interference waves propagating over tens of microns.

Contribution

It offers the first experimental evidence connecting photoluminescence blinking to lattice wave interference in InGaN quantum wells, supported by a theoretical model.

Findings

Observed low-frequency interference waves in photoluminescence

Demonstrated wave propagation over tens of microns

Proposed thermal vibrations cause blinking phenomena

Abstract

The photoluminescence of III-V wide band-gap semiconductors as InGaN is characterized by local intensity fluctuations, known as 'blinking points', that despite decades of research are not yet completely understood. In this letter we report experimental data and a theoretical interpretation that suggests they are caused by the interference of thermal vibrations of the Quantum Well lattice. With far-field optical tests we could observe the lower frequency tail of these interference waves and study their dynamics as they propagate up to distances of several tens of microns.