Demonstration of detuned dual recycling at the Garching 30 m laser interferometer

Dual recycling is an advanced optical technique to enhance the signal-to-no ise ratio of laser interferometric gravitational wave detectors in a limite d bandwidth. To optimise the center of this band with respect to Fourier fr equencies of expected gravitational wave signals, detuned dual recycling ha s to be implemented. We have demonstrated detuned dual recycling on a fully suspended 30 m prototype interferometer. A control scheme that allows the detector to be tuned to different frequencies will be outlined. Good agreem ent between the experimental results and numerical simulations has been ach ieved. (C) 2000 Elsevier Science B.V. All rights reserved.