Arm-length stabilisation for interferometric gravitational-wave detectors using frequency-doubled auxiliary lasers

Adam J. Mullavey; Bram J. J. Slagmolen; John Miller; Matthew Evans; Peter Fritschel; Daniel Sigg; Sam J. Waldman; Daniel A. Shaddock; David E. McClelland

doi:10.1364/oe.20.000081

arXiv · 1112.3118

Arm-length stabilisation for interferometric gravitational-wave detectors using frequency-doubled auxiliary lasers

Adam J. Mullavey·Bram J. J. Slagmolen·John Miller·Matthew Evans·Peter Fritschel·Daniel Sigg·Sam J. Waldman·Daniel A. Shaddock·David E. McClelland

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Abstract

Residual motion of the arm cavity mirrors is expected to prove one of the principal impediments to systematic lock acquisition in advanced gravitational-wave interferometers. We present a technique which overcomes this problem by employing auxiliary lasers at twice the fundamental measurement frequency to pre-stabilise the arm cavities' lengths. Applying this approach, we reduce the apparent length noise of a 1.3 m long, independently suspended Fabry-Perot cavity to 30 pm rms and successfully transfer longitudinal control of the system from the auxiliary laser to the measurement laser.

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Adam J. Mullavey, Bram J. J. Slagmolen, John Miller, Matthew Evans, Peter Fritschel, Daniel Sigg, Sam J. Waldman, Daniel A. Shaddock, David E. McClelland. 2011-12-14. Arm-length stabilisation for interferometric gravitational-wave detectors using frequency-doubled auxiliary lasers. https://doi.org/10.1364/oe.20.000081

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