Dispersion properties of high-Q passive and active single or coupled resonators

Abstract

conference 7226 « Advances in Slow and Fast Light II », Topic : Advanced Quantum and Optoelectronic Applications, Session: 6 : « Slow and Fast Light in Microresonators » [7226-28]International audienceWe present a simple method to determine simultaneously the transmission and dispersive properties of passive or active high Q-factor optical resonators. The method is based on cavity ring down spectroscopy where the probe wavelength is rapidly swept across the resonance. It has already been shown that this technique allows the loaded cavity lifetime of passive resonators to be obtained. Here we show that we can also infer the dispersion introduced by the resonator and the resonant gain in the case of active resonators. The method is tested on a model system consisting of fiber resonators. We applied the method to measure the intrinsic Q-factor of a passive MgF2 whispering gallery mode resonator. We also used it to characterize the high Q-factor of a system of coupled fiber resonators. Finally we show that the method can be used to determine the gain and dispersive properties of selective amplifiers such as Er3+ doped fiber resonators