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Experimental Demonstration of Unconditional Entanglement Swapping for Continuous Variables

Xiaojun Jia·Xiaolong Su·Qing Pan·Jiangrui Gao·Changde Xie·Kunchi Peng
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Abstract

The unconditional entanglement swapping for continuous variables is experimentally demonstrated. Two initial entangled states are produced from two nondegenerate optical parametric amplifiers operating at deamplification. Through implementing the direct measurement of Bell-state between two optical beams from each amplifier the remaining two optical beams, which have never directly interacted with each other, are entangled. The quantum correlation degrees of 1.23dB and 1.12dB below the shot noise limit for the amplitude and phase quadratures resulting from the entanglement swapping are straightly measured.

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Xiaojun Jia, Xiaolong Su, Qing Pan, Jiangrui Gao, Changde Xie, Kunchi Peng. 2004-12-25. Experimental Demonstration of Unconditional Entanglement Swapping for Continuous Variables. https://doi.org/10.1103/physrevlett.93.250503

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