Physical Review Letters

Increasing the Astrophysical Reach of the Advanced Virgo Detector via the Application of Squeezed Vacuum States of Light

F. Acernese, M. Agathos, L. Aiello, A. Allocca, A. Amato, Stefano Ansoldi, S. Antier, M. Arène, N. Arnaud, S. Ascenzi, P. Astone, F. Aubin, S. Babak, Philippe Bacon, F. Badaracco, M. K. M. Bader, J. Baird, F. Baldaccini, Giulio Ballardin, G. Baltus, C. Barbieri, P. Barneo, F. Barone, M. Barsuglia, D. Barta, A. Basti, M. Bawaj, M. Bazzan, M. Bejger, I. Belahcene, Sebastiano Bernuzzi, D. Bersanetti, Alessandro Bertolini, M. Bischi, M. Bitossi, M. A. Bizouard, F. Bobba, M. Boër, G. Bogaert, F. Bondu, Romain Bonnand, Boris A. Boom, Valerio Boschi, Y. Bouffanais, A. Bozzi, C. Bradaschia, M. Branchesi, M. Breschi, Tristan Briant, Fabrizio Brighenti, Alain Brillet, J. Brooks, G. Bruno, T. Bulik, Henk Jan Bulten, Damir Buskulic, Gianpietro Cagnoli C, Enrico Calloni, M. Canepa, Giovanni Carapella, Franco Carbognani, G. Carullo, J. Casanueva Diaz, C. Casentini, J. Castañeda, S. Caudill, F. Cavalier, R. Cavalieri, Giancarlo Cella, Pablo Cerdá-Durán, E. Cesarini, O. Chaibi, Eric Chassande-Mottin, F. Chiadini, R. Chierici, A. Chincarini, A. Chiummo, Nelson L Christensen, S. Chua, G. Ciani, P. Ciecieląg, M. Cieślar, R. Ciolfi, F. Cipriano, A. Cirone, Sébastien Clesse, F. Cleva, E. Coccia, P.-F. Cohadon, D. Cohen, Monica Colpi, L. Conti, I. Cordero-Carrión, S. Corezzi, D. Corre, S. Cortese, J.‐P. Coulon, M. Croquette, J. R. Cudell, E. Cuoco

Published Dec 5, 2019• 430 citations

Publisher

Abstract

Current interferometric gravitational-wave detectors are limited by quantum noise over a wide range of their measurement bandwidth. One method to overcome the quantum limit is the injection of squeezed vacuum states of light into the interferometer's dark port. Here, we report on the successful application of this quantum technology to improve the shot noise limited sensitivity of the Advanced Virgo gravitational-wave detector. A sensitivity enhancement of up to 3.2±0.1 dB beyond the shot noise limit is achieved. This nonclassical improvement corresponds to a 5%-8% increase of the binary neutron star horizon. The squeezing injection was fully automated and over the first 5 months of the third joint LIGO-Virgo observation run O3 squeezing was applied for more than 99% of the science time. During this period several gravitational-wave candidates have been recorded.

DOI: 10.1103/physrevlett.123.231108

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