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arXiv · 1903.05901

Conditional dynamics of optomechanical two-tone backaction-evading measurements

Matteo Brunelli·Daniel Malz·Andreas Nunnenkamp
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Abstract

Backaction-evading measurements of mechanical motion can achieve precision below the zero-point uncertainty and quantum squeezing, which makes them a resource for quantum metrology and quantum information processing. We provide an exact expression for the conditional state of an optomechanical system in a two-tone backaction-evading measurement beyond the standard adiabatic approximation and perform extensive numerical simulations to go beyond the usual rotating-wave approximation. We predict the simultaneous presence of conditional mechanical squeezing, intra-cavity squeezing, and optomechanical entanglement. We further apply an analogous analysis to the multimode optomechanical system of two mechanical and one cavity mode and find conditional mechanical Einstein-Podolski-Rosen entanglement and genuinely tripartite optomechanical entanglement. Our analysis is of direct relevance for state-of-the-art optomechanical experiments that have entered the backaction-dominated regime.

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Matteo Brunelli, Daniel Malz, Andreas Nunnenkamp. 2019-03-14. Conditional dynamics of optomechanical two-tone backaction-evading measurements. https://doi.org/10.1103/physrevlett.123.093602

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