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arXiv · 1109.2381

Feedback Enhanced Sensitivity in Optomechanics: Surpassing the Parametric Instability Barrier

Glen I. Harris·Ulrik L. Andersen·Joachim Knittel·Warwick P. Bowen
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Abstract

The intracavity power, and hence sensitivity, of optomechanical sensors is commonly limited by parametric instability. Here we characterize the parametric instability induced sensitivity degradation in a micron scale cavity optomechanical system. Feedback via optomechanical transduction and electrical gradient force actuation is applied to suppress the parametric instability. As a result a 5.4 fold increase in mechanical motion transduction sensitivity is achieved to a final value of $1.9\times 10^{-18}\rm m Hz^{-1/2}$.

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Glen I. Harris, Ulrik L. Andersen, Joachim Knittel, Warwick P. Bowen. 2011-09-12. Feedback Enhanced Sensitivity in Optomechanics: Surpassing the Parametric Instability Barrier. https://doi.org/10.1103/physreva.85.061802

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