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Phase-matched four wave mixing and quantum beam splitting of matter waves in a periodic potential

Karen Marie Hilligsøe·Klaus Mølmer
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Abstract

We show that the dispersion properties imposed by an external periodic potential ensure both energy and quasi-momentum conservation such that correlated pairs of atoms can be generated by four wave mixing from a Bose-Einstein condensate moving in an optical lattice potential. In our numerical solution of the Gross-Pitaevskii equation, a condensate with initial quasi-momentum k_0 is transferred almost completely (>95%) into a pair of correlated atomic components with quasi-momenta k_1 and k_2, if the system is seeded with a smaller number of atoms with the appropriate quasi-momentum k_1.

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Karen Marie Hilligsøe, Klaus Mølmer. 2005-03-22. Phase-matched four wave mixing and quantum beam splitting of matter waves in a periodic potential. https://doi.org/10.1103/physreva.71.041602

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