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arXiv · 1007.0403

A continuous-variable formalism for the Faraday atom-light interface

Julia Stasińska·Simone Paganelli·Carles Rodó·Anna Sanpera
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Abstract

Quantum interfaces between polarized atomic ensembles and coherent states of light, applied recently to manipulate bipartite and multipartite entanglement, are revisited by means of a continuous-variable formalism. The explicit use of the continuous-variable formalism facilitates significantly the analysis of entanglement between different modes, reducing it to the study of the properties of a final covariance matrix which can be found analytically. Furthermore, it allows to study matter-light interfaces for mixed states, adapting the formalism to the experimental situations in which the initial prepared Gaussian states are, unavoidably, affected by a certain amount of noise. A multipartite scenario, leading to the generation of macroscopic cluster states is presented and analyzed in detail within this formalism.

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Julia Stasińska, Simone Paganelli, Carles Rodó, Anna Sanpera. 2011-06-25. A continuous-variable formalism for the Faraday atom-light interface. https://arxiv.org/abs/1007.0403

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