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

W. H. Wang·S. Ghosh·F. M. Mendoza·X. Li·D. D. Awschalom·N. Samarth
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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 $β\sim 0.09$. 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.

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W. H. Wang, S. Ghosh, F. M. Mendoza, X. Li, D. D. Awschalom, N. Samarth. 2005-01-20. Static and Dynamic Spectroscopy of (Al,Ga)As/GaAs Microdisk Lasers with Interface Fluctuation Quantum Dots. https://doi.org/10.1103/physrevb.71.155306

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