Efficient wavelength conversion in novel integrated structures

In this work we first demonstrated, by means of C-MOS compatible Hydex R glass based micro ring resonators, efficient wavelength conversion by FWM using ultra-low continuous-wave pump power (<5 mW, λ 1553.38 nm). In this first set of experiments, we used rings whose Q factor was 65,000 and whose free spectral range was 575 GHz. By using the experimental value of the FWM efficiency we estimated the nonlinear refractive index (n2) of Hydex waveguides to be as much as five times larger than that of standard Silica, and the nonlinear γ parameter to be around 250 times higher than that of typical single mode glass fibers. Furthermore, the overall field enhancement factor of our device was shown to be ≅ 1.4·10⁷, much larger than in semiconductor structures where losses tend to be in the order of several dB/cm. Our results are comparable to the highest values reported to date in silicon ring resonators, and in addition they combine the advantages of ultra-low optical loss (0.06 dB/cm) with the absence of two-photon absorption (near λ = 1.5 μm). We believe that these achievements may bring us a step forward in the quest to create very efficient all optical communication networks. (authors)