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arXiv · 1906.01295

A macrorealistic test in hybrid quantum optomechanics

Marta Maria Marchese·Hannah McAleese·Angelo Bassi·Mauro Paternostro
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Abstract

We discuss a scheme for macrorealistic theories of the Leggett-Garg form [A. J. Leggett and A. Garg, Phys. Rev. Lett. 54, 857 (1985)]. Our scheme is based on a hybrid optomechanical system. It seems reasonable to test these inequalities with an optomechanical system, since in an optomechanical cavity it is possible to create non-classical states of the mirror through a projective measurement on the cavity field. We will present the protocol to generate such non-classicality for a general optomechanical cavity and after we will carry out a theoretical test for one of the possible formulations of these inequalities using a hybrid optomechanical system. Specifically, the inequality will be investigated for an harmonic oscillator coupled to a two-level system, which replaces the light field of the cavity. The aim is to reproduce, with this system, the evolution of a single spin-1/2 for which the inequality is violated; this is achievable through the conditioning of the two-level system which will be used as an ancilla.

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Marta Maria Marchese, Hannah McAleese, Angelo Bassi, Mauro Paternostro. 2019-06-04. A macrorealistic test in hybrid quantum optomechanics. https://doi.org/10.1088/1361-6455/ab6d18

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