Physical Review Letters

Frequency-Dependent Squeezed Vacuum Source for the Advanced Virgo Gravitational-Wave Detector

F. Acernese, M. Agathos, A. Ain, Simone Albanesi, C Alléné, A. Allocca, A. Amato, Claude Amra, M. Andia, T Andrade, Nicolás Andrés, Marc Andrés-Carcasona, T. Andrić, Stefano Ansoldi, S. Antier, Theocharis A. Apostolatos, E. Z. Appavuravther, M. Arène, N. Arnaud, M. Assiduo, S. Assis de Souza Melo, P. Astone, F. Aubin, S. Babak, F. Badaracco, S. Bagnasco, J. Baird, Tomasz Baka, Giulio Ballardin, G. Baltus, B. Banerjee, P. Barneo, F. Barone, M. Barsuglia, D. Barta, A. Basti, M. Bawaj, M. Bazzan, F. Beirnaert, M. Bejger, V. Benedetto, M. Berbel, Sebastiano Bernuzzi, D. Bersanetti, Alessandro Bertolini, U. Bhardwaj, A. Bianchi, Maciej Bilicki, S. Bini, M. Bischi, M. Bitossi, M. A. Bizouard, F. Bobba, M. Boër, G. Bogaert, Guillaume Boileau, Mattia Boldrini, L. D. Bonavena, R. Bondarescu, F. Bondu, Romain Bonnand, Valerio Boschi, V. Boudart, Y. Bouffanais, A. Bozzi, C. Bradaschia, Matteo Braglia, M. Branchesi, M. Breschi, Tristan Briant, Alain Brillet, J. Brooks, Giuseppe Eugenio Bruno, F. Bucci, Oleg M Bulashenko, T. Bulik, Henk Jan Bulten, R. Buscicchio, Damir Buskulic, C. Buy, G. Cabras, Ricardo Cabrita, Gianpietro Cagnoli C, Enrico Calloni, M. Canepa, G. Caneva Santoro, M. Cannavacciuolo, E. Capocasa, Giovanni Carapella, Franco Carbognani, M. Carpinelli, G. Carullo, J. Casanueva Diaz, C. Casentini, S. Caudill, R. Cavalieri, G. Cella, Pablo Cerdá-Durán, E. Cesarini, Walid Chaibi

Published Jul 25, 2023• 41 citations

Publisher

Abstract

In this Letter, we present the design and performance of the frequency-dependent squeezed vacuum source that will be used for the broadband quantum noise reduction of the Advanced Virgo Plus gravitational-wave detector in the upcoming observation run. The frequency-dependent squeezed field is generated by a phase rotation of a frequency-independent squeezed state through a 285 m long, high-finesse, near-detuned optical resonator. With about 8.5 dB of generated squeezing, up to 5.6 dB of quantum noise suppression has been measured at high frequency while close to the filter cavity resonance frequency, the intracavity losses limit this value to about 2 dB. Frequency-dependent squeezing is produced with a rotation frequency stability of about 6 Hz rms, which is maintained over the long term. The achieved results fulfill the frequency dependent squeezed vacuum source requirements for Advanced Virgo Plus. With the current squeezing source, considering also the estimated squeezing degradation induced by the interferometer, we expect a reduction of the quantum shot noise and radiation pressure noise of up to 4.5 dB and 2 dB, respectively.

DOI: 10.1103/physrevlett.131.041403

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