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Squeezed Fock state by inconclusive photon subtraction

Stefano Olivares·Matteo G. A. Paris
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Abstract

We analyze in details the properties of the conditional state recently obtained by J. Wenger, et al. [Phys. Rev. Lett. {\bf 92}, 153601 (2004)] by means of inconclusive photon subtraction (IPS) on a squeezed vacuum state $S(r)\ket{0}$. The IPS process can be characterized by two parameters: the IPS transmissivity $τ$ and the photodetection quantum efficiency $η$. We found that the conditional state approaches the squeezed Fock state $S(r)\ket{1}$ when $τ,η\to 1$, i.e., in the limit of single-photon subtraction. For non-unit IPS transmissivity and efficiency, the conditioned state remains close to the target state, {\em i.e.} shows a high fidelity for a wide range of experimental parameters. The nonclassicality of the conditional state is also investigated and a nonclassicality threshold on the IPS parameters is derived.

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Stefano Olivares, Matteo G. A. Paris. 2005-06-14. Squeezed Fock state by inconclusive photon subtraction. https://doi.org/10.1088/1464-4266/7/12/025

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