Squeezing the quantum noise of a gravitational-wave detector below the standard quantum limit

• DOI: 10.1126/science.ado8069
• Publication Date: 2024-09-19T18:00:23Z
• Authors: Wenxuan Jia; Victoria Xu; Kevin Kuns; Masayuki Nakano; Lisa Barsotti; Matthew Evans; Nergis Mavalvala; ; R. Abbott; I. Abouelfettouh; R. X. Adhikari; A. Ananyeva; S. Appert; K. Arai; N. Aritomi; S. M. Aston; M. Ball; S. W. Ballmer; D. Barker; B. K. Berger; J. Betzwieser; D. Bhattacharjee; G. Billingsley; N. Bode; E. Bonilla; V. Bossilkov; A. Branch; A. F. Brooks; D. D. Brown; J. Bryant; C. Cahillane; H. Cao; E. Capote; Y. Chen; F. Clara; J. Collins; C. M. Compton; R. Cottingham; D. C. Coyne; R. Crouch; J. Csizmazia; T. J. Cullen; L. P. Dartez; N. Demos; E. Dohmen; J. C. Driggers; S. E. Dwyer; A. Effler; A. Ejlli; T. Etzel; J. Feicht; R. Frey; W. Frischhertz; P. Fritschel; V. V. Frolov; P. Fulda; M. Fyffe; D. Ganapathy; B. Gateley; J. A. Giaime; K. D. Giardina; J. Glanzer; E. Goetz; A. W. Goodwin-Jones; S. Gras; C. Gray; D. Griffith; H. Grote; T. Guidry; E. D. Hall; J. Hanks; J. Hanson; M. C. Heintze; A. F. Helmling-Co...; H. Y. Huang; Y. Inoue; A. L. James; A. Jennings; S. Karat; M. Kasprzack; K. Kawabe; N. Kijbunchoo; J. S. Kissel; A. Kontos; R. Kumar; M. Landry; B. Lantz; M. Laxen; K. Lee; M. Lesovsky; F. Llamas; M. Lormand; H. A. Loughlin; R. Macas; M. MacInnis; C. N. Makarem; B. Mannix; G. L. Mansell; R. M. Martin; N. Maxwell; G. McCarrol; R. McCarthy; D. E. McClelland; S. McCormick; L. McCuller; T. McRae; F. Mera; E. L. Merilh; F. Meylahn; R. Mittleman; D. Moraru; G. Moreno; M. Mould; A. Mullavey; T. J. N. Nelson; A. Neunzert; J. Oberling; T. O’Hanlon; C. Osthelder; D. J. Ottaway; H. Overmier; W. Parker; A. Pele; H. Pham; M. Pirello; V. Quetschke; K. E. Ramirez; J. Reyes; J. W. Richardson; M. Robinson; J. G. Rollins; J. H. Romie; M. P. Ross; T. Sadecki; A. Sanchez; E. J. Sanchez; L. E. Sanchez; R. L. Savage; D. Schaetzl; M. G. Schiworski; R. Schnabel; R. M. S. Schofield; E. Schwartz; D. Sellers; T. Shaffer; R. W. Short; D. Sigg; B. J. J. Slagmolen; S. Soni; L. Sun; D. B. Tanner; M. Thomas; P. Thomas; K. A. Thorne; C. I. Torrie; G. Traylor; G. Vajente; J. Vanosky; A. Vecchio; P. J. Veitch; A. M. Vibhute; E. R. G. von Reis; J. Warner; B. Weaver; R. Weiss; C. Whittle; B. Willke; C. C. Wipf; H. Yamamoto; H. Yu; L. Zhang; M. E. Zucker
• Keywords: Quantum Physics; Physics - Instrumentation and Detectors; FOS: Physical sciences; General Relativity and Quantum Cosmology (gr-qc); Instrumentation and Detectors (physics.ins-det); Astrophysics - Instrumentation and Methods for Astrophysics; Quantum Physics (quant-ph); Instrumentation and Methods for Astrophysics (astro-ph.IM); General Relativity and Quantum Cosmology

The Heisenberg uncertainty principle dictates that the position and momentum of an object cannot be simultaneously measured with arbitrary precision, giving rise to an apparent limitation known as the standard quantum limit (SQL). Gravitational-wave detectors use photons to continuously measure the positions of freely falling mirrors and so are affected by the SQL. We investigated the performance of the Laser Interferometer Gravitational-Wave Observatory (LIGO) after the experimental realization of frequency-dependent squeezing designed to surpass the SQL. For the LIGO Livingston detector, we found that the upgrade reduces quantum noise below the SQL by a maximum of three decibels between 35 and 75 hertz while achieving a broadband sensitivity improvement, increasing the overall detector sensitivity during astrophysical observations.