title: Generation of continuous variable Einstein-Podolsky-Rosen entanglement via the Kerr nonlinearity in an optical fiber.
abstract: We report on the generation of a continuous variable Einstein-Podolsky-Rosen (EPR) entanglement using an optical fiber interferometer. The Kerr nonlinearity in the fiber 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 is 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.
authors.affiliation: Zentrum für Moderne Optik, Universität Erlangen-Nürnberg, Staudtstrasse 7/B2, D-91058 Erlangen, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Silberhorn
authors.forename: P K
authors.initials: PK
authors.lastname: Lam
authors.forename: O
authors.initials: O
authors.lastname: Weiss
authors.forename: F
authors.initials: F
authors.lastname: König
authors.forename: N
authors.initials: N
authors.lastname: Korolkova
authors.forename: G
authors.initials: G
authors.lastname: Leuchs