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arXiv · 1704.03571

Control and tuning of a suspended Fabry-Perot cavity using digitally-enhanced heterodyne interferometry

John Miller·Silvie Ngo·Adam J. Mullavey·Bram J. J. Slagmolen·Daniel A. Shaddock·David E. McClelland
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Abstract

We present the first demonstration of real-time closed-loop control and deterministic tuning of an independently suspended Fabry-Perot optical cavity using digitally-enhanced heterodyne interferometry, realising a peak sensitivity of $\sim$10 pm$/\sqrt{\mathrm{Hz}}$ over the 10-1000 Hz frequency band. The methods presented are readily extensible to multiple coupled cavities. As such, we anticipate that refinements of this technique may find application in future interferometric gravitational-wave detectors.

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John Miller, Silvie Ngo, Adam J. Mullavey, Bram J. J. Slagmolen, Daniel A. Shaddock, David E. McClelland. 2017-04-11. Control and tuning of a suspended Fabry-Perot cavity using digitally-enhanced heterodyne interferometry. https://doi.org/10.1364/ol.37.004952

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