title: Broadband squeezing of quantum noise in a Michelson interferometer with Twin-Signal-Recycling.
abstract: Twin-Signal-Recycling (TSR) builds on the resonance doublet of two optically coupled cavities and efficiently enhances the sensitivity of an interferometer at a dedicated signal frequency. We report on what we believe to be the first experimental realization of a TSR Michelson interferometer and also its broadband enhancement by squeezed light injection. The complete setup was stably locked, and a broadband quantum noise reduction of the interferometers shot noise by a factor of up to 4 dB was demonstrated. The system was characterized by measuring its quantum noise spectra for several tunings of the TSR cavities. We found good agreement between the experimental results and numerical simulations.
authors.affiliation: Institut for Gravitationsphysik, Leibniz Universität Hannover, Hannover, Germany. andre.thuering@aei.mpg.de
authors.forename: André
authors.initials: A
authors.lastname: Thüring
authors.forename: Christian
authors.initials: C
authors.lastname: Gräf
authors.forename: Henning
authors.initials: H
authors.lastname: Vahlbruch
authors.forename: Moritz
authors.initials: M
authors.lastname: Mehmet
authors.forename: Karsten
authors.initials: K
authors.lastname: Danzmann
authors.forename: Roman
authors.initials: R
authors.lastname: Schnabel