  Adiabatic wavelength conversion is experimentally demonstrated at a single
photon power-level using an integrated Silicon ring resonator. This approach
allows conversion of a photon to arbitrary wavelengths with no energy or phase
matching constraints. The conversion is inherently low-noise and efficient with
greater than 10% conversion efficiencies for wavelength changes up to 0.5nm,
more than twenty times the resonators line-width. The observed wavelength
change and efficiency agrees well with theory and bright coherent light
demonstrations. These results will enable integrated quantum optical wavelength
conversion for application ranging from wavelength-multiplexed quantum networks
to frequency bin entanglement.
