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arXiv · 0805.1993

Full characterization of Gaussian bipartite entangled states by a single homodyne detector

V. D'Auria·S. Fornaro·A. Porzio·S. Solimeno·S. Olivares·M. G. A. Paris
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Abstract

We present the full experimental reconstruction of Gaussian entangled states generated by a type--II optical parametric oscillator (OPO) below threshold. Our scheme provides the entire covariance matrix using a single homodyne detector and allows for the complete characterization of bipartite Gaussian states, including the evaluation of purity, entanglement and nonclassical photon correlations, without a priori assumptions on the state under investigation. Our results show that single homodyne schemes are convenient and robust setups for the full characterization of OPO signals and represent a tool for quantum technology based on continuous variable entanglement.

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V. D'Auria, S. Fornaro, A. Porzio, S. Solimeno, S. Olivares, M. G. A. Paris. 2009-01-16. Full characterization of Gaussian bipartite entangled states by a single homodyne detector. https://doi.org/10.1103/physrevlett.102.020502

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