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arXiv quant-ph/04040492004-04quant-ph

Multipartite continuous-variable entanglement from concurrent nonlinearities

Olivier Pfister, Sheng Feng, Gregory Jennings, Raphael Pooser, Daruo Xie

备注：: Accepted by Phys. Rev. A. 4 pages, 2 figures. V.3: minor typos corrected, one reference added
发表信息：: Phys. Rev. A 70, 020302(R) (2004)
DOI：: 10.1103/PhysRevA.70.020302

英文摘要：

We show theoretically that concurrent interactions in a second-order nonlinear medium placed inside an optical resonator can generate multipartite entanglement between the resonator modes. We show that there is a mathematical connexion between this system and van Loock and Braunstein's proposal for entangling N continuous quantum optical variables by interfering the outputs of N degenerate optical parametric amplifiers (OPA) at a N-port beam splitter. Our configuration, however, requires only one nondegenerate OPA and no interferometer. In a preliminary experimental study, we observe the concurrence of the appropriate interactions in periodically poled RbTiOAsO4.

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