An experimental demonstration of resonant sideband extraction for laser-interferometric gravitational wave detectors

Resonant sideband extraction is a new optical configuration for laser-interferometric gravitational wave detectors with Fabry-Perot cavities in the arms. It reduces the thermal load on the beam splitter and the coupling mirrors of the cavities and also allows one to adapt the frequency response of the detector to a variety of requirements. We report the first experimental demonstration using a table-top setup at a detuned operating point. An increase of sensitivity by 6 dB was observed for artificial signals at frequencies above the arm cavity bandwidth, and the overall transfer function agreed well with theoretical predictions.