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arXiv · 1207.5012

Witnessing non-classicality of a quantum oscillator state by coupling it to a qubit

S. Agarwal·J. H. Eberly
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Abstract

We propose a new witness operation for the non-classical character of a harmonic oscillator state. The method does not require state reconstruction. For all harmonic oscillator states that are classical, a bound is established for the evolution of a qubit which is coupled to the oscillator. Any violation of the bound can be rigorously attributed to the non-classical character of the initial oscillator state.

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S. Agarwal, J. H. Eberly. 2012-07-20. Witnessing non-classicality of a quantum oscillator state by coupling it to a qubit. https://doi.org/10.1103/physreva.86.022341

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