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High-sensitivity optical measurement of mechanical Brownian motion

Y. Hadjar·P. F. Cohadon·C. G. Aminoff·M. Pinard·A. Heidmann
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Abstract

We describe an experiment in which a laser beam is sent into a high-finesse optical cavity with a mirror coated on a mechanical resonator. We show that the reflected light is very sensitive to small mirror displacements. We have observed the Brownian motion of the resonator with a very high sensitivity.

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Y. Hadjar, P. F. Cohadon, C. G. Aminoff, M. Pinard, A. Heidmann. 1999-09-03. High-sensitivity optical measurement of mechanical Brownian motion. https://doi.org/10.1209/epl%2Fi1999-00422-6

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