We examined a concentric Si nanocrystal (Si-nc) and Er doped SiO2 (Er: SiO2) microdisk structure supporting high-Q whispering gallery modes (WGMs) at both visible and telecom wavelengths. This structure provides a means to utilize Si-nc luminescence as an optical pump for an Er: SiO2 cavity without subjecting a telecom-wavelength, Er: SiO2-based mode to loss mechanisms associated with the Si-nc material. After fabricating a concentric microdisk consisting of an inner Si-nc disk and an outer Er: SiO2 ring, we characterize visible wavelength WGMs excited by the Si-nc photoluminescence and observed spectrometer limited quality factors as high as 10(3). Telecom-wavelength photoluminescence from the Er: SiO2 ring was measured to have a quality factor as high as 10(4) in the erbium luminescence region using a passive pulled fiber setup.
