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arXiv · 2105.10510

Improving force sensitivity by amplitude measurement of light reflected from a detuned optomechanical cavity

Kentaro Komori·Takuya Kawasaki·Sotatsu Otabe·Yutaro Enomoto·Yuta Michimura·Masaki Ando
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Abstract

The measurement of weak continuous forces exerted on a mechanical oscillator is a fundamental problem in various physical experiments. It is fundamentally impeded by quantum back-action from the meter used to sense the displacement of the oscillator. In the context of interferometric displacement measurements, we here propose and demonstrate the working principle of a scheme for coherent back-action cancellation. By measuring the amplitude quadrature of the light reflected from a detuned optomechanical cavity inside which a stiff optical spring is generated, back-action can be cancelled in a narrow band of frequencies. This method provides a simple way to improve the sensitivity in experiments limited by quantum back-action without injection of squeezed light or stable homodyne readout.

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Kentaro Komori, Takuya Kawasaki, Sotatsu Otabe, Yutaro Enomoto, Yuta Michimura, Masaki Ando. 2021-05-21. Improving force sensitivity by amplitude measurement of light reflected from a detuned optomechanical cavity. https://doi.org/10.1103/physreva.104.l031501

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