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arXiv · 1209.6334

Observation of Radiation Pressure Shot Noise on a Macroscopic Object

T. P. Purdy·R. W. Peterson·C. A. Regal
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Abstract

The quantum mechanics of position measurement of a macroscopic object is typically inaccessible because of strong coupling to the environment and classical noise. Here we monitor a mechanical resonator subject to an increasingly strong continuous position measurement and observe a quantum mechanical backaction force that rises in accordance with the Heisenberg uncertainty limit. For our optically-based position measurements, the backaction takes the form of a fluctuating radiation pressure from the Poisson-distributed photons in the coherent measurement field, termed radiation pressure shot noise. We demonstrate a backaction force that is comparable in magnitude to the thermal forces in our system. Additionally, we observe a temporal correlation between fluctuations in the radiation force and in the position of the resonator.

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T. P. Purdy, R. W. Peterson, C. A. Regal. 2013-02-17. Observation of Radiation Pressure Shot Noise on a Macroscopic Object. https://doi.org/10.1126/science.1231282

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