Quantum Dot-Microdisk Cavities in the InGaN/GaN Material System

Quantum dots (QDs) coupled to high quality nanocavities have served as outstanding platforms for understanding cavity quantum electrodynamics (cQED) in solid state systems. Such coupled QDs embedded within microdisks or photonic crystal cavities in the GaAs material system have demonstrated single photons on demand, enhanced radiative emission and strong coupling. Similar achievements in other material systems have proven to be more challenging, both in the quality of the materials and thus in the quality factors achievable for cavities formed from those materials. Our studies in the nitride materials comprise a variety of QD densities, microdisk thicknesses and direct comparisons with quantum well structures. By tracking the related cavity quality factors and the lasing thresholds of these QD-microdisk systems, we can come to a better understanding of the important factors in material quality and structural design that lead to the lowest lasing thresholds, and ultimately to the best coupling between QDs and cavity.