High-Q whispering-gallery modes in GaAs∕AlOx microdisks

Abstract

We report on the fabrication of microdisks on an AlOx pedestal. We develop a process using electron beam lithography, a chemical etching, and selective oxidation. InAs self-assembled quantum dots are used as a broad band source to probe the optical modes of the microdisks. With this process, we observe whispering-gallery modes, with quality factors as large as 12 500 for 2-μm-diam microdisks.