Advanced interferometer configurations
Variable Reflectivity Signal Recycling Mirror for Advanced Gravitational Wave Interferometers
Signal recycling could be extended to an even more complex configuration by replacing the signal recycling mirror with a short cavity that acts as a variable reflectivity signal recycling mirror. Although not planned for second generation gravitational wave detectors, the addition of a variable reflectivity signal recycling mirror at the output of the detector remains an option when upgrading second generation detectors. The addition of this length degree of freedom at the transmitted port of the Michelson interferometer increases the detector and control system complexity but allows tailoring of both the interferometer bandwidth and frequency of peak sensitivity. The goal of work completed at the Centre for Gravitational Physics was to create a control system for a dual recycled Michelson interferometer with a variable reflectivity signal recycling mirror.