Ultra-low power frequency conversion in two-photon-absorption free micro ring resonator

All-optical integrated circuits bring the promise to vastly increase the bandwidth, improve the flexibility as well as reduce the cost of future communication networks. All op- tical integrated components, like switches and wavelength converters, must meet fundamental requirements such as low optical losses, strong nonlinear response and ease of fabrication. To date, however, research on these devices has been based either on semiconductors, such as silicon and GaAs, or highly nonlinear glasses, such as chalcogenides which, although exhibit a Kerr nonlinearity (n2) of 100x-400x silica glass, also present limitations such as remarkable linear and nonlinear losses and, for certain applications, a not developed fabrication techniques. Specifically, the possibility to rely upon a mature technology recently has proved itself to be a powerful so- lution to fabricate micrometric resonant structures which are able to locally enhance the desired nonlinearities. In this work we present the first example of nonlinear optics in silica glass waveg- uides using continuous wave (CW) light. We achieve wavelength conversion via four wave mixing (FWM) at ultra-low (≈ 5mW CW) power levels in C-MOS compatible micro-ring resonator.