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Intensity correlations and entanglement by frequency doubling in a dual ported resonator

Oo-Kaw Lim·Mark Saffman
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Abstract

We show that non-classical intensity correlations and quadrature entanglement can be generated by frequency doubling in a resonator with two output ports. We predict twin-beam intensity correlations 6 dB below the coherent state limit, and that the product of the inference variances of the quadrature fluctuations gives an Einstein-Podolsky-Rosen (EPR) correlation coefficient of V_EPR = 0.6 < 1. Comparison with an entanglement source based on combining two frequency doublers with a beam splitter shows that the dual ported resonator provides stronger entanglement at lower levels of individual beam squeezing. Calculations are performed using a self-consistent propagation method that does not invoke a mean field approximation. Results are given for physically realistic parameters that account for the Gaussian shape of the intracavity beams, as well as intracavity losses.

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Oo-Kaw Lim, Mark Saffman. 2006-03-09. Intensity correlations and entanglement by frequency doubling in a dual ported resonator. https://doi.org/10.1103/physreva.74.023816

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