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Multipartite continuous-variable entanglement from concurrent nonlinearities

Olivier Pfister·Sheng Feng·Gregory Jennings·Raphael Pooser·Daruo Xie
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Abstract

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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Olivier Pfister, Sheng Feng, Gregory Jennings, Raphael Pooser, Daruo Xie. 2004-08-19. Multipartite continuous-variable entanglement from concurrent nonlinearities. https://doi.org/10.1103/physreva.70.020302

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