Strong Purcell effect for InAs quantum boxes in high-Q wet-etched microdisks

We report on the fabrication of high-quality GaAs microdisks using a new two-step wet-etching fabrication process, and on their optical characterization, using the photoluminescence of InAs Quantum Boxes as an intracavity light source. We measure quality factors as high as 12 000 for the resonant whispering gallery modes, which highlights an excellent smoothness of the cavity sidewalls. Those small-volume/high-Q-confined modes are extremely attractive for performing CQED experiments on solid-state emitters. Using a novel experimental approach, we could in particular observe a record enhancement of the SE rate for emitters on-resonance with such modes (×18), in a cw PL experiment.