Physical Review Letters

Quantum-Enhanced Advanced LIGO Detectors in the Era of Gravitational-Wave Astronomy

M. Tse, Haocun Yu, N. Kijbunchoo, Álvaro Fernández-Galiana, Peter Dupej, L. Barsotti, Carl D. Blair, D. D. Brown, S. E. Dwyer, A. Effler, M. Evans, Peter K Fritschel, V. V. Frolov, A. C. Green, Georgia L. Mansell, Fabrice Matichard, N. Mavalvala, David E. McClelland, Lee P. McCuller, T. McRae, John Miller, Adam J. Mullavey, Eric Glenn Oelker, Isabelle Phinney, Daniel Sigg, Bram J. J. Slagmolen, T. Vo, Robert L. Ward, Chris Whittle, R. Abbott, C. Adams, R. X. Adhikari, A. Ananyeva, S. Appert, Koji Arai, J. S. Areeda, Y. Asali, S. M. Aston, Corey Austin, A. M. Baer, Matthew Ball, S. W. Ballmer, S. Banagiri, D. Barker, J. Bartlett, B. K. Berger, J. Betzwieser, D. Bhattacharjee, G. Billingsley, S. Biscans, R. M. Blair, Nina Bode, Phillip Booker, R. Bork, A. Bramley, Aidan F. Brooks, A. Buikema, C. Cahillane, K. C. Cannon, X. Chen, A. A. Ciobanu, F. Clara, S. J. Cooper, K. R. Corley, S. T. Countryman, P. B. Covas, D. C. Coyne, L. E. H. Datrier, D. Davis, Chiara Di Fronzo, J. C. Driggers, T. Etzel, T. M. Evans, Jon R. Feicht, P. Fulda, M. Fyffe, J. A. Giaime, K. D. Giardina, P. Godwin, E. Goetz, S. Gras, C. Gray, R. Gray, Anchal Gupta, Eric K. Gustafson, R. Gustafson, J. Hanks, J. Hanson, Terra Hardwick, R. K. Hasskew, Matthew C. Heintze, Adrian F. Helmling-Cornell, N. A. Holland, J. D. Jones, S. Kandhasamy, S. Karki, M. Kasprzack, K. Kawabe, P. J. King, Jeffrey S Kissel

Published Dec 5, 2019• 663 citations

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Abstract

The Laser Interferometer Gravitational Wave Observatory (LIGO) has been directly detecting gravitational waves from compact binary mergers since 2015. We report on the first use of squeezed vacuum states in the direct measurement of gravitational waves with the Advanced LIGO H1 and L1 detectors. This achievement is the culmination of decades of research to implement squeezed states in gravitational-wave detectors. During the ongoing O3 observation run, squeezed states are improving the sensitivity of the LIGO interferometers to signals above 50 Hz by up to 3 dB, thereby increasing the expected detection rate by 40% (H1) and 50% (L1).

DOI: 10.1103/physrevlett.123.231107

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