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arXiv · 1302.0867

Quantum-enhanced micro-mechanical displacement sensitivity

Ulrich B. Hoff·Glen I. Harris·Lars S. Madsen·Hugo Kerdoncuff·Mikael Lassen·Bo M. Nielsen·Warwick P. Bowen·Ulrik L. Andersen
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Abstract

We report on a hitherto unexplored application of squeezed light: for quantum-enhancement of mechanical transduction sensitivity in microcavity optomechanics. Using a toroidal silica microcavity, we experimentally demonstrate measurement of the transduced phase modulation signal with a sensitivity $-0.72(\pm 0.01)$\,dB below the shot noise level. This is achieved for resonant probing in the highly under-coupled regime, by preparing the probe in a weak coherent state with phase squeezed vacuum states at sideband frequencies.

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Ulrich B. Hoff, Glen I. Harris, Lars S. Madsen, Hugo Kerdoncuff, Mikael Lassen, Bo M. Nielsen, Warwick P. Bowen, Ulrik L. Andersen. 2013-02-04. Quantum-enhanced micro-mechanical displacement sensitivity. https://doi.org/10.1364/ol.38.001413

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