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Quantum variational measurement in the next generation gravitational-wave detectors

F. Ya. Khalili
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Abstract

A relatively simple method of overcoming the Standard Quantum Limit in the next-generation Advanced LIGO gravitational wave detector is considered. It is based on the quantum variational measurement with a single short (a few tens of meters) filter cavity. Estimates show that this method allows to reduce the radiation pressure noise at low frequencies ($<100 \mathrm{Hz}$) to the level comparable with or smaller than the low-frequency noises of non-quantum origin (mirrors suspension noise, mirrors internal thermal noise, and gravity gradients fluctuations).

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F. Ya. Khalili. 2007-02-07. Quantum variational measurement in the next generation gravitational-wave detectors. https://doi.org/10.1103/physrevd.76.102002

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