Static and Dynamic Spectroscopy of (Al,Ga)As/GaAs Microdisk Lasers with Interface Fluctuation Quantum Dots

TL;DR

This study investigates the optical properties of (Al,Ga)As/GaAs microdisk lasers with interface fluctuation quantum dots, revealing their steady-state and dynamic behaviors, mode interactions, and effects of processing on decay rates.

Contribution

It provides new insights into the optical dynamics and mode behavior of microdisk lasers with interface fluctuation quantum dots, including measurements of quality factor, coupling constant, and decay rates.

Findings

Quality factor Q ~ 5600

Mode hopping observed with temperature and power

Decay rates increase with excitation power

Abstract

We have studied the steady state and dynamic optical properties of semiconductor microdisk lasers whose active region contains interface fluctuation quantum dots in GaAs/(Ga,Al)As quantum wells. Steady-state measurements of the stimulated emission via whispering gallery modes yield a quality factor $Q \sim 5600$ and a coupling constant $\beta \sim 0.09$. The broad gain spectrum produces mode hopping between spectrally adjacent whispering gallery modes as a function of temperature and excitation power. Time- and energy-resolved photoluminescence measurements show that the emission rise and decay rates increase significantly with excitation power. Marked differences are observed between the radiative decay rates in processed and unprocessed samples.