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Optical noise correlations and beating the standard quantum limit in advanced gravitational-wave detectors

Alessandra Buonanno·Yanbei Chen
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Abstract

The uncertainty principle, applied naively to the test masses of a laser-interferometer gravitational-wave detector, produces a Standard Quantum Limit (SQL) on the interferometer's sensitivity. It has long been thought that beating this SQL would require a radical redesign of interferometers. However, we show that LIGO-II interferometers, currently planned for 2006, can beat the SQL by as much as a factor two over a bandwidth Δf \sim f, if their thermal noise can be pushed low enough. This is due to dynamical correlations between photon shot noise and radiation-pressure noise, produced by the LIGO-II signal-recycling mirror.

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Alessandra Buonanno, Yanbei Chen. 2001-07-06. Optical noise correlations and beating the standard quantum limit in advanced gravitational-wave detectors. https://doi.org/10.1088/0264-9381%2F18%2F15%2F102

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