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arXiv · 1003.1357

Continuous variable entanglement enhancement and manipulation by a sub-threshold type-II optical parametric amplifier

Yana Shang·Xiaojun Jia·Yumei Shen·Changde Xie·Kunchi Peng
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Abstract

We experimentally demonstrate that the quantum entanglement between amplitude and phase quadratures of optical modes produced from a non-degenerate optical parametric amplifier (NOPA) can be enhanced and manipulated phase-sensitively by means of another NOPA. When both NOPAs operate at de-amplification, the entanglement degree is increased at the cavity resonance of the second NOPA. When the first NOPA operates at de-amplification and the second one at amplification, the spectral features of the correlation variances are significantly changed. The experimental results are in good agreement with the theoretical expectation.

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Yana Shang, Xiaojun Jia, Yumei Shen, Changde Xie, Kunchi Peng. 2010-03-06. Continuous variable entanglement enhancement and manipulation by a sub-threshold type-II optical parametric amplifier. https://doi.org/10.1364/ol.35.000853

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