We determine the theoretical limits to squeezing-enhanced measurement sensitivity of mechanical motion in a cavity optomechanical system. The motion of a mechanical resonator is transduced onto quadrature fluctuations of a cavity optical field and a measurement is performed on the optical field exiting the cavity. We compare measurement sensitivities obtained with coherent probing and quantum-enhanced probing of the mechanical motion, i.e. the coherent probe field carries vacuum states and quadrature squeezed vacuum states at sideband frequencies, respectively. We find that quantum-enhanced probing provides little to no improvement in motion sensing for resonators in the unresolved sideband regime but may significantly increase measurement sensitivities for resonators in the resolved sideband regime.
@article{arxiv.1611.09772,
title = {Squeezing-enhanced measurement sensitivity in a cavity optomechanical system},
author = {Hugo Kerdoncuff and Ulrich B. Hoff and Glen I. Harris and Warwick P. Bowen and Ulrik L. Andersen},
journal= {arXiv preprint arXiv:1611.09772},
year = {2016}
}