Imperfect Fabry-Perot resonators
Abstract
The initial goal of this thesis was to demonstrate chaos in an open two-mirror resonator. We have designed a bifocal mirror that forms a resonator with an unstable inner and a stable outer part. To be able to distinguish phenomena unique for configuration from phenomena also present in conventional resonators, i.e., roughness-induced scattering and aberrations, the performance of a conventional stable resonator is investigated first. Roughness-induced scattering turns out to affect the cavity finesse as well as the average power throughput and produces mode coupling close to frequency-degenerate points. We demonstrate, furthermore, a method to accurately determine aberrations by measuring the Gouy phase of subsequent higher-order modes around frequency-degeneracy. The bifocal mirror is not fabricated by traditional grinding and polishing, but by diamond-machining. The eigenmodes of a resonator with one diamond-machined bifocal mirror turn out to be Laguerre-Gaussian. We demonstrate furthermore, the coupling of two resonators based on transmission spectra and patterns, and report on the ability of the configuration to fulfill the basic requirements to obtain chaos.

