Observation of Disorder State Coupling to Excitons in InGaN Disks in GaN Nanowires

TL;DR

This study investigates how background disorder states in InGaN disks within GaN nanowires influence exciton dynamics, revealing rapid non-radiative decay pathways that could enhance device brightness.

Contribution

It provides new insights into exciton-disorder coupling in InGaN/GaN nanowires, highlighting the role of disorder states in exciton decay processes.

Findings

Exciton emission dominates optical response.

Disorder states strongly couple with excitons.

Rapid non-radiative decay from disorder states observed.

Abstract

InxGa1-xN disks in GaN nanowires (DINWs) have emerged as a viable technology for on-chip tunable visible spectrum emission without the use of a phosphor. Here we present a study of the optical emission and absorption dynamics in DINWs that incorporates the important role of background disorder states. We show that the optical emission in the system is dominated by quantum-confined excitons, however the exci-tons are coupled to a large density of background disorder states. Rapid non-radiative decay (compared to other decay rates such as spontaneous emission) from disorder states into excitons is observed after optical excitation of our sample, which can be advantageous for increasing the brightness of the system in future design efforts.