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arXiv · cond-mat/0304527

Extended molecules and geometric scattering resonances in optical lattices

P. O. Fedichev·M. J. Bijlsma·P. Zoller
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Abstract

We develop a theory describing neutral atoms scattering at low energies in an optical lattice. We show that for a repulsive interaction, as the microscopic scattering length increases, the effective scattering amplitude approaches a limiting value which depends only on the lattice parameters. In the case of attractive interaction a geometric resonance occurs before reaching this limit. Close to the resonance, the effective interaction becomes repulsive and supports a weakly bound state, which can extend over several lattice sites.

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P. O. Fedichev, M. J. Bijlsma, P. Zoller. 2003-04-23. Extended molecules and geometric scattering resonances in optical lattices. https://doi.org/10.1103/physrevlett.92.080401

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