High-Q Whispering Gallery Modes in Wet Etched Silica Microdisk Resonators Containing Silicon Nanocrystals

We demonstrate coupling of room temperature photoluminescence (PL) emission from silicon nanocrystals (nc-Si) embedded in silicon-rich silicon oxide (SRSO) to whispering gallery modes (WGMs) of 10 mum radius microdisk resonators. The resonators were fabricated by wet chemical etching of circular patterns defined by electron beam lithography and display very smooth edges. We observe nearly degenerate counter-propagating WGMs from the microdisks and measure quality factors of Q>3500 for the fundamental mode at 850 nm - limited by the absorption loss from the nanocrystals