GaN-based Bipolar Cascade Lasers with 25nm wide Quantum Wells: Simulation and Analysis

TL;DR

This paper investigates GaN-based bipolar cascade lasers with wide quantum wells, revealing their potential for polarization screening and gain, while identifying key performance limitations like absorption and heating.

Contribution

It introduces a novel analysis of wide quantum wells in GaN lasers, challenging assumptions and exploring their impact on device physics and performance.

Findings

Wide quantum wells enable polarization screening and gain from higher levels.

Internal absorption and self-heating significantly limit laser performance.

Performance optimization options are discussed based on simulation results.

Abstract

We analyze internal device physics, performance limitations, and optimization options for a unique laser design with multiple active regions separated by tunnel junctions, featuring surprisingly wide quantum wells. Contrary to common assumptions, these quantum wells are revealed to allow for perfect screening of the strong built-in polarization field, while optical gain is provided by higher quantum levels. However, internal absorption, low p-cladding conductivity, and self-heating are shown to strongly limit the laser performance.