Optical resonators metrology using an RF-spectrum approach

International audienceA Microwave domain characterization technique is proposed to measure the optical properties of high quality factor optical resonators, featuring a very high precision in frequency which can be as good as 1 Hz. It aims to acquire a full knowledge of the complex transfer function (amplitude and phase) characterizing these resonators. It is shown that the amplitude response gives access to the measure of several parameters like the free spectral range and the quality factor. Moreover the phase transition at the resonance is used to define the coupling regime and to calculate the resonator parameters: transmission coefficient and intra-cavity losses