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arXiv · 1910.11892

Back-action evading impulse measurement with mechanical quantum sensors

Sohitri Ghosh·Daniel Carney·Peter Shawhan·Jacob M. Taylor
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Abstract

The quantum measurement of any observable naturally leads to noise added by the act of measurement. Approaches to evade or reduce this noise can lead to substantial improvements in a wide variety of sensors, from laser interferometers to precision magnetometers and more. In this paper, we develop a measurement protocol based upon pioneering work by the gravitational wave community which allows for reduction of added noise from measurement by coupling an optical field to the momentum of a small mirror. As a specific implementation, we present a continuous measurement protocol using a double-ring optomechanical cavity. We demonstrate that with experimentally-relevant parameters, this protocol can lead to significant back-action noise evasion, yielding measurement noise below the standard quantum limit over many decades of frequency.

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Sohitri Ghosh, Daniel Carney, Peter Shawhan, Jacob M. Taylor. 2019-10-25. Back-action evading impulse measurement with mechanical quantum sensors. https://doi.org/10.1103/physreva.102.023525

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