



01337nas a2200157   4500008004100000245007600041210006900117260001400186490000800200520085400208100001901062700001901081700001901100700001901119856004101138       2020                        eng d00aBack-action evading impulse measurement with mechanical quantum sensors0 aBackaction evading impulse measurement with mechanical quantum s  c8/28/20200 v1023 a<p>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.</p>1 aGhosh, Sohitri1 aCarney, Daniel1 aShawhan, Peter1 aTaylor, J., M.  uhttps://arxiv.org/pdf/1910.11892.pdf