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Quantum correlations between light and the kilogram-mass mirrors of LIGO

Yu, Haocun and McCuller, L. and Tse, M. and Barsotti, L. and Mavalvala, N. and Betzwieser, J. and Blair, C. D. and Dwyer, S. E. and Effler, A. and Evans, M. and Fernandez-Galiana, A. and Fritschel, P. and Frolov, V. V. and Kijbunchoo, N. and Matichard, F. and McClelland, D. E. and McRae, T. and Mullavey, A. and Sigg, D. and Slagmolen, B. J. J. and Whittle, C. and Buikema, A. and Chen, Y. and Corbitt, T. R. and Schnabel, R. and Abbott, R. and Adams, C. and Adhikari, R. X. and Ananyeva, A. and Appert, S. and Arai, K. and Areeda, J. S. and Asali, Y. and Aston, S. M. and Austin, C. and Baer, A. M. and Ball, M. and Ballmer, S. W. and Banagiri, S. and Barker, D. and Bartlett, J. and Berger, B. K. and Bhattacharjee, D. and Billingsley, G. and Biscans, S. and Blair, R. M. and Bode, N. and Booker, P. and Bork, R. and Bramley, A. and Brooks, A. F. and Brown, D. D. and Cahillane, C. and Cannon, K. C. and Chen, X. and Ciobanu, A. A. and Clara, F. and Cooper, S. J. and Corley, K. R. and Countryman, S. T. and Covas, P. B. and Coyne, D. C. and Datrier, L. E. H. and Davis, D. and Fronzo, C. Di and Dooley, K. L. and Driggers, J. C. and Dupej, P. and Etzel, T. and Evans, T. M. and Feicht, J. and Fulda, P. and Fyffe, M. and Giaime, J. A. and Giardina, K. D. and Godwin, P. and Goetz, E. and Gras, S. and Gray, C. and Gray, R. and Green, A. C. and Gupta, Anchal and Gustafson, E. K. and Gustafson, R. and Hanks, J. and Hanson, J. and Hardwick, T. and Hasskew, R. K. and Heintze, M. C. and Helmling-Cornell, A. F. and Holland, N. A. and Jones, J. D. and Kandhasamy, S. and Karki, S. and Kasprzack, M. and Kawabe, K. and King, P. J. and Kissel, J. S. and Kumar, Rahul and Landry, M. and Lane, B. B. and Lantz, B. and Laxen, M. and Lecoeuche, Y. K. and Leviton, J. and Liu, J. and Lormand, M. and Lundgren, A. P. and Macas, R. and MacInnis, M. and Macleod, D. M. and Mansell, G. L. and Márka, S. and Márka, Z. and Martynov, D. V. and Mason, K. and Massinger, T. J. and McCarthy, R. and McCormick, S. and McIver, J. and Mendell, G. and Merfeld, K. and Merilh, E. L. and Meylahn, F. and Mistry, T. and Mittleman, R. and Moreno, G. and Mow-Lowry, C. M. and Mozzon, S. and Nelson, T. J. N. and Nguyen, P. and Nuttall, L. K. and Oberling, J. and Oram, Richard J. and Osthelder, C. and Ottaway, D. J. and Overmier, H. and Palamos, J. R. and Parker, W. and Payne, E. and Pele, A. and Perez, C. J. and Pirello, M. and Radkins, H. and Ramirez, K. E. and Richardson, J. W. and Riles, K. and Robertson, N. A. and Rollins, J. G. and Romel, C. L. and Romie, J. H. and Ross, M. P. and Ryan, K. and Sadecki, T. and Sanchez, E. J. and Sanchez, L. E. and Saravanan, T. R. and Savage, R. L. and Schaetzl, D. and Schofield, R. M. S. and Schwartz, E. and Sellers, D. and Shaffer, T. and Smith, J. R. and Soni, S. and Sorazu, B. and Spencer, A. P. and Strain, K. A. and Sun, L. and Szczepańczyk, M. J. and Thomas, M. and Thomas, P. and Thorne, K. A. and Toland, K. and Torrie, C. I. and Traylor, G. and Urban, A. L. and Vajente, G. and Valdes, G. and Vander-Hyde, D. C. and Veitch, P. J. and Venkateswara, K. and Venugopalan, G. and Viets, A. D. and Vo, T. and Vorvick, C. and Wade, M. and Ward, R. L. and Warner, J. and Weaver, B. and Weiss, R. and Willke, B. and Wipf, C. C. and Xiao, L. and Yamamoto, H. and Yu, Hang and Zhang, L. and Zucker, M. E. and Zweizig, J. (2020) Quantum correlations between light and the kilogram-mass mirrors of LIGO. Nature, 583 (7814). pp. 43-47. ISSN 0028-0836.

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[img] Image (JPEG) (Extended Data Fig. 1: Spectral density measurements revealing sub-SQL quantum noise of the interferometer with uncertainties) - Supplemental Material
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[img] Image (JPEG) (Extended Data Fig. 2: Squeezing level of the interferometer over the full range of squeezing angles) - Supplemental Material
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[img] Image (JPEG) (Extended Data Fig. 3: Individual and combined estimates of non-stationary noise between measurement segments) - Supplemental Material
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[img] Image (JPEG) (Extended Data Table 1 Interferometer and squeezer parameters used for modelling the Advanced LIGO detector in Livingston) - Supplemental Material
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The measurement of minuscule forces and displacements with ever greater precision is inhibited by the Heisenberg uncertainty principle, which imposes a limit to the precision with which the position of an object can be measured continuously, known as the standard quantum limit. When light is used as the probe, the standard quantum limit arises from the balance between the uncertainties of the photon radiation pressure applied to the object and of the photon number in the photoelectric detection. The only way to surpass the standard quantum limit is by introducing correlations between the position/momentum uncertainty of the object and the photon number/phase uncertainty of the light that it reflects. Here we confirm experimentally the theoretical prediction that this type of quantum correlation is naturally produced in the Laser Interferometer Gravitational-wave Observatory (LIGO). We characterize and compare noise spectra taken without squeezing and with squeezed vacuum states injected at varying quadrature angles. After subtracting classical noise, our measurements show that the quantum mechanical uncertainties in the phases of the 200-kilowatt laser beams and in the positions of the 40-kilogram mirrors of the Advanced LIGO detectors yield a joint quantum uncertainty that is a factor of 1.4 (3 decibels) below the standard quantum limit. We anticipate that the use of quantum correlations will improve not only the observation of gravitational waves, but also more broadly future quantum noise-limited measurements.

Item Type:Article
Related URLs:
URLURL TypeDescription ReadCube access Paper
Chen, Y.0000-0002-9730-9463
Adhikari, R. X.0000-0002-5731-5076
Arai, K.0000-0001-8916-8915
Billingsley, G.0000-0002-4141-2744
Biscans, S.0000-0002-9635-7527
Brooks, A. F.0000-0003-4295-792X
Coyne, D. C.0000-0002-6427-3222
Gupta, Anchal0000-0002-1762-9644
McIver, J.0000-0003-0316-1355
Richardson, J. W.0000-0002-1472-4806
Sun, L.0000-0001-7959-892X
Vajente, G.0000-0002-7656-6882
Xiao, L.0000-0003-2703-449X
Zhang, L.0000-0002-0898-787X
Zucker, M. E.0000-0002-2544-1596
Zweizig, J.0000-0002-1521-3397
Alternate Title:Quantum correlations between the light and kilogram-mass mirrors of LIGO
Additional Information:© 2020 The Author(s), under exclusive licence to Springer Nature Limited. Received 03 February 2020; Accepted 04 May 2020; Published 01 July 2020. LIGO was constructed by the California Institute of Technology and the Massachusetts Institute of Technology with funding from the National Science Foundation, and operates under Cooperative Agreement number PHY-1764464. Advanced LIGO was built under grant number PHY-0823459. The authors gratefully acknowledge the support of the Australian Research Council under the ARC Centre of Excellence for Gravitational Wave Discovery grant number CE170100004, Linkage Infrastructure, Equipment and Facilities grant number LE170100217 and Discovery Early Career Award number DE190100437; the National Science Foundation Graduate Research Fellowship under grant number 1122374; the Science and Technology Facilities Council of the United Kingdom; and the LIGO Scientific Collaboration Fellows programme. Data availability: Source data for Figs. 2, 3, Extended Data Figs. 1–3 and other data pertaining to this study are available from the corresponding authors upon reasonable request. Author Contributions: The measurements presented in this paper were performed with the 4-km detector at the LIGO Livingston Observatory using a novel squeezed light source. Haocun Yu performed all of the measurements. Haocun Yu and L.M. carried out the analysis of the data. M. Tse, Haocun Yu and N.K. built and commissioned the squeezed-light sources. L.B. led the squeezed-light upgrade of the LIGO detectors, involving contributions from a large number of people within the LIGO Laboratory, the Australian National University and other members of the LIGO Scientific Collaboration. N.M. led the experimental campaign to measure sub-SQL quantum noise in the Advanced LIGO detector. Haocun Yu, L.M., M. Tse, L.B. and N.M. contributed directly to the preparation of the manuscript. The authors declare no competing interests.
Funding AgencyGrant Number
Australian Research CouncilCE170100004
Australian Research CouncilLE170100217
Australian Research CouncilDE190100437
NSF Graduate Research FellowshipDGE-1122374
Science and Technology Facilities Council (STFC)UNSPECIFIED
LIGO Scientific Collaboration FellowsUNSPECIFIED
Subject Keywords:Astronomy and astrophysics; Quantum physics
Issue or Number:7814
Record Number:CaltechAUTHORS:20200424-112847161
Persistent URL:
Official Citation:Yu, H., McCuller, L., Tse, M. et al. Quantum correlations between light and the kilogram-mass mirrors of LIGO. Nature 583, 43–47 (2020).
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:102777
Deposited By: Tony Diaz
Deposited On:24 Apr 2020 18:50
Last Modified:07 Jul 2020 17:50

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