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arXiv · 1508.04700

Audio-band frequency-dependent squeezing

Eric Oelker·Tomoki Isogai·John Miller·Maggie Tse·Lisa Barsotti·Nergis Mavalvala·Matthew Evans
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Abstract

Quantum vacuum fluctuations impose strict limits on precision displacement measurements, those of interferometric gravitational-wave detectors among them. Introducing squeezed states into an interferometer's readout port can improve the sensitivity of the instrument, leading to richer astrophysical observations. However, optomechanical interactions dictate that the vacuum's squeezed quadrature must rotate by 90 degrees around 50Hz. Here we use a 2-m-long, high-finesse optical resonator to produce frequency-dependent rotation around 1.2kHz. This demonstration of audio-band frequency-dependent squeezing uses technology and methods that are scalable to the required rotation frequency, heralding application of the technique in future gravitational-wave detectors.

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Eric Oelker, Tomoki Isogai, John Miller, Maggie Tse, Lisa Barsotti, Nergis Mavalvala, Matthew Evans. 2015-08-18. Audio-band frequency-dependent squeezing. https://doi.org/10.1103/physrevlett.116.041102

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