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arXiv · 2301.00338

Unification of thermal and quantum noise in gravitational-wave detectors

Chris Whittle·Lee McCuller·Vivishek Sudhir·Matthew Evans
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Abstract

Contemporary gravitational-wave detectors are fundamentally limited by thermal noise -- due to dissipation in the mechanical elements of the test mass -- and quantum noise -- from the vacuum fluctuations of the optical field used to probe the test mass position. Two other fundamental noises can in principle also limit sensitivity: test-mass quantization noise due to the zero-point fluctuation of its mechanical modes, and thermal excitation of the optical field. We use the quantum fluctuation-dissipation theorem to unify all four noises. This unified picture shows precisely when test-mass quantization noise and optical thermal noise can be ignored.

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Chris Whittle, Lee McCuller, Vivishek Sudhir, Matthew Evans. 2023-01-01. Unification of thermal and quantum noise in gravitational-wave detectors. https://doi.org/10.1103/physrevlett.130.241401

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