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Experimental generation of 6 dB continuous variable entanglement from a nondegenerate optical parametric amplifier

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 Added by Xiaolong Su
 Publication date 2010
  fields Physics
and research's language is English




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We experimentally demonstrated that the quantum correlations of amplitude and phase quadratures between signal and idler beams produced from a non-degenerate optical parametric amplifier (NOPA) can be significantly improved by using a mode cleaner in the pump field and reducing the phase fluctuations in phase locking systems. Based on the two technical improvements the quantum entanglement measured with a two-mode homodyne detector is enhanced from ~ 4 dB to ~ 6 dB below the quantum noise limit using the same NOPA and nonlinear crystal.



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