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arXiv:quant-ph/0412106 · Physical Review A

Entanglement and the Einstein-Podolsky-Rosen paradox with coupled intracavity optical down-converters

M. K. Olsen, P. D. Drummond

Published May 10, 2005• 23 citations
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Abstract

We show that two evanescently coupled ${\ensuremath{\chi}}^{(2)}$ parametric down-converters inside a Fabry-Perot cavity provide a tunable source of quadrature squeezed light, Einstein-Podolsky-Rosen (EPR) correlations and quantum entanglement. Analyzing the operation in the below threshold regime, we show how these properties can be controlled by adjusting the coupling strengths and the cavity detunings. As this can be implemented with integrated optics, it provides a possible route to rugged and stable EPR sources.

DOI
10.1103/physreva.71.053803

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We show theoretically that two evanescently coupled χ(2)χ^{(2)}χ(2) second harmonic generators inside a Fabry-Perot cavity provide a tunable source of quadrature squeezed light, Einstein-Podolsky-Rosen correlations and quantum entanglement. Unlike systems using coupled downconverters, second harmonic generation has no oscillation threshhold, so that the entangled fields become macroscopically occupied as soon as the pumping fields are turned on. This system also gives two frequencies at which the entangled fields can have macroscopic intensity. We show how the entanglement properties can be controlled by adjusting the pumping, the coupling strengths and the cavity detunings.
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