Coupling of high-quality-factor optical resonators
Résumé
Optical resonators with high quality factor (Q-factor) present a great interest for several applications in optoelectronic, metrology or fundamental physics. They can, for instance, be used in optical filtering, all optical switching, low threshold non-linear optics, etc. Main results have been obtained since 1996. Recently results have been obtained with mono-crystalline such as MgF2, Quartz or CaF2 whispering gallery mode (WGM) resonators. Rare-earth doped micro spheres are tiny lasers which intrinsically offer narrow line width emission. To characterize the resonators, there is the need to realize a good coupling. Although we improve theoretically and experimentally the problem of the coupling between a high Q-factor resonator and its external coupler. They are characterized by different methods such as slow and fast frequency sweeping. Resonators can be coupled to tapered fibres or prisms. We focus here on characterizations techniques of passive optical resonators or active (Erbium doped ZBLALiP) WGM resonators in terms of Q-factor determination.