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arXiv · 1103.4199

Demonstrating various quantum effects with two entangled laser beams

B. Hage·J. Janoušek·S. Armstrong·T. Symul·J. Bernu·H. M. Chrzanowski·P. K. Lam·H. A. Bachor
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Abstract

We report on the preparation of entangled two mode squeezed states of yet unseen quality. Based on a measurement of the covariance matrix we found a violation of the Reid and Drummond EPR-criterion at a value of only 0.36\pm0.03 compared to the threshold of 1. Furthermore, quantum state tomography was used to extract a single photon Fock state solely based on homodyne detection, demonstrating the strong quantum features of this pair of laser-beams. The probability for a single photon in this ensemble measurement exceeded 2/3.

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B. Hage, J. Janoušek, S. Armstrong, T. Symul, J. Bernu, H. M. Chrzanowski, P. K. Lam, H. A. Bachor. 2011-05-02. Demonstrating various quantum effects with two entangled laser beams. https://doi.org/10.1140/epjd%2Fe2011-20153-9

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