Enhanced sensitivity of the LIGO gravitational wave detector by using squeezed states of light

Nearly a century after Einstein first predicted the existence of gravitational waves, a global network of Earth-based gravitational wave observatories1,2,3,4 is seeking to directly detect this faint radiation using precision laser interferometry. Photon shot noise, due to the quantum nature of light, imposes a fundamental limit on the attometre-level sensitivity of the kilometre-scale Michelson interferometers deployed for this task. Here, we inject squeezed states to improve the performance of one of the detectors of the Laser Interferometer Gravitational-Wave Observatory (LIGO) beyond the quantum noise limit, most notably in the frequency region down to 150 Hz, critically important for several astrophysical sources, with no deterioration of performance observed at any frequency. With the injection of squeezed states, this LIGO detector demonstrated the best broadband sensitivity to gravitational waves ever achieved, with important implications for observing the gravitational-wave Universe with unprecedented sensitivity Fil: Aasi, J.. California Institute of Technology; Estados Unidos Fil: Abadie, J.. California Institute of Technology; Estados Unidos Fil: Abbott, P.. California Institute of Technology; Estados Unidos Fil: Abbott, R.. California Institute of Technology; Estados Unidos Fil: Abbott, T. D.. State University of Louisiana; Estados Unidos Fil: Kozameh, Carlos Nicolas. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Winkelmann, L.. Max Planck Institut f¨ur Gravitationsphysik; Alemania. Leibniz Universit¨at Hannover; Alemania Fil: Winkler, W.. Max Planck Institut f¨ur Gravitationsphysik; Alemania. Leibniz Universit¨at Hannover; Alemania Fil: Wip, C. C.. Massachusetts Institute of Technology; Estados Unidos Fil: Wittel, H.. Max Planck Institut f¨ur Gravitationsphysik; Alemania. Leibniz Universit¨at Hannover; Alemania Fil: Woan, G.. University of Glasgow; Reino Unido Fil: Wooley, R.. Livingston Observatory; Estados Unidos Fil: Worden, J.. Hanford Observatory; Estados Unidos Fil: Yablon, J.. Northwestern University; Estados Unidos Fil: Yakushin, I.. Livingston Observatory; Estados Unidos Fil: Yamamoto, H.. California Institute of Technology; Estados Unidos Fil: Yancey, C. C.. University of Maryland; Estados Unidos Fil: Yang, H.. Caltech-CaRT; Estados Unidos Fil: Yeaton Massey, D.. California Institute of Technology; Estados Unidos Fil: Yoshida, S.. Southeastern Louisiana University; Estados Unidos Fil: Yum, H.. Northwestern University; Estados Unidos Fil: Zanolin, M.. Embry-Riddle Aeronautical University; Estados Unidos Fil: Zhang, F.. Massachusetts Institute of Technology; Estados Unidos Fil: Zhang, L.. California Institute of Technology; Estados Unidos Fil: Zhao, C.. University of Western Australia; Australia Fil: Zhu, H.. State University of Pennsylvania; Estados Unidos Fil: Zhu, X. J.. University of Western Australia; Australia Fil: Zotov, N.. Louisiana Tech University; Estados Unidos Fil: Zucker, M. E.. Massachusetts Institute of Technology; Estados Unidos Fil: Zweizig, J.. California Institute of Technology; Estados Unidos