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arXiv · 0706.2036

Observation of back-action cancellation in interferometric and weak force measurements

T. Caniard·P. Verlot·T. Briant·P. -F. Cohadon·A. Heidmann
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Abstract

We experimentally demonstrate a cancellation of back-action noise in optical measurements. Back-action cancellation was first proposed within the framework of gravitational-wave detection by dual resonators as a way to drastically improve their sensitivity. We have developed an experiment based on a high-finesse Fabry-Perot cavity to study radiation-pressure effects in ultra-sensitive displacement measurements. Using an intensity-modulated intracavity field to mimic the quantum radiation-pressure noise, we report the first observation of back-action cancellation due to a destructive interference between radiation-pressure effects on both mirrors of the cavity. We have observed a sensitivity improvement by a factor larger than 20 both in displacement and weak force measurements.

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T. Caniard, P. Verlot, T. Briant, P. -F. Cohadon, A. Heidmann. 2007-06-14. Observation of back-action cancellation in interferometric and weak force measurements. https://doi.org/10.1103/physrevlett.99.110801

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