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Generation of Continuous Variable Einstein-Podolsky-Rosen Entanglement via the Kerr Nonlinearity in an Optical Fibre

Ch. Silberhorn·P. K. Lam·O. Weiss·F. Koenig·N. Korolkova·G. Leuchs
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Abstract

We report on the generation of a continuous variable Einstein-Podolsky-Rosen (EPR) entanglement using an optical fibre interferometer. The Kerr nonlinearity in the fibre is exploited for the generation of two independent squeezed beams. These interfere at a beam splitter and EPR entanglement is obtained between the output beams. The correlation of the amplitude (phase) quadratures are measured to be 4.0+-0.2 (4.0+-0.4) dB below the quantum noise limit. The sum criterion for these squeezing variances 0.80+-0.03 < 2 verifies the nonseparability of the state. The product of the inferred uncertainties for one beam 0.64+-0.08 is well below the EPR limit of unity.

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Ch. Silberhorn, P. K. Lam, O. Weiss, F. Koenig, N. Korolkova, G. Leuchs. 2001-03-01. Generation of Continuous Variable Einstein-Podolsky-Rosen Entanglement via the Kerr Nonlinearity in an Optical Fibre. https://doi.org/10.1103/physrevlett.86.4267

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