TY - JOUR

T1 - First Demonstration of 6 dB Quantum Noise Reduction in a Kilometer Scale Gravitational Wave Observatory

AU - Lough, J. D.

AU - Schreiber, E.

AU - Bergamin, Fabio

AU - Grote, Hartmut

AU - Mehmet, Moritz

AU - Vahlbruch, Henning

AU - Affeldt, Christoph

AU - Brinkmann, Marc

AU - Bisht, Aparna

AU - Kringel, Volker

AU - Lück, Harald

AU - Sorazu, Borja

AU - Strain, Kenneth

AU - Mukund, N.

AU - Nadji, S. L.

AU - Weinert, M.

AU - Danzmann, Karsten

N1 - Funding Information: The authors would like to thank Walter Grass for his years of expert support in the maintenance of critical infrastructure to the site to include the extensive vacuum system. The authors are grateful for support from the Science and Technology Facilities Council Grant Ref: ST/L000946/1, the University of Glasgow in the United Kingdom, the Bundesministerium für Bildung und Forschung, the state of Lower Saxony in Germany, the Max Planck Society, Leibniz Universität Hannover, and Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy—EXC 2123 QuantumFrontiers—390837967. This work was partly supported by DFG grant SFB/Transregio 7 Gravitational Wave Astronomy. This document has been assigned LIGO document number LIGO-P2000032.

PY - 2021/1/26

Y1 - 2021/1/26

N2 - Photon shot noise, arising from the quantum-mechanical nature of the light, currently limits the sensitivity of all the gravitational wave observatories at frequencies above one kilohertz. We report a successful application of squeezed vacuum states of light at the GEO 600 observatory and demonstrate for the first time a reduction of quantum noise up to 6.03±0.02 dB in a kilometer scale interferometer. This is equivalent at high frequencies to increasing the laser power circulating in the interferometer by a factor of 4. Achieving this milestone, a key goal for the upgrades of the advanced detectors required a better understanding of the noise sources and losses and implementation of robust control schemes to mitigate their contributions. In particular, we address the optical losses from beam propagation, phase noise from the squeezing ellipse, and backscattered light from the squeezed light source. The expertise gained from this work carried out at GEO 600 provides insight toward the implementation of 10 dB of squeezing envisioned for third-generation gravitational wave detectors.

AB - Photon shot noise, arising from the quantum-mechanical nature of the light, currently limits the sensitivity of all the gravitational wave observatories at frequencies above one kilohertz. We report a successful application of squeezed vacuum states of light at the GEO 600 observatory and demonstrate for the first time a reduction of quantum noise up to 6.03±0.02 dB in a kilometer scale interferometer. This is equivalent at high frequencies to increasing the laser power circulating in the interferometer by a factor of 4. Achieving this milestone, a key goal for the upgrades of the advanced detectors required a better understanding of the noise sources and losses and implementation of robust control schemes to mitigate their contributions. In particular, we address the optical losses from beam propagation, phase noise from the squeezing ellipse, and backscattered light from the squeezed light source. The expertise gained from this work carried out at GEO 600 provides insight toward the implementation of 10 dB of squeezing envisioned for third-generation gravitational wave detectors.

UR - http://www.scopus.com/inward/record.url?scp=85100262096&partnerID=8YFLogxK

U2 - 10.1103/PhysRevLett.126.041102

DO - 10.1103/PhysRevLett.126.041102

M3 - Article

VL - 126

JO - Physical review letters

JF - Physical review letters

SN - 0031-9007

IS - 4

M1 - 041102

ER -