Physical Review A

Mean-field approach to dipole-dipole interaction in an optical lattice

C. Menotti, Helmut Ritsch

Published Oct 1, 1999• 8 citations

Abstract

We compare the influence of quantum statistics and atom-atom interaction in bright and dark one-dimensional optical lattices for atoms using quantum rate equations. Via a Hartree-Fock--type mean-field approach we derive an effective nonlinear single-atom equation and solve it self-consistently for a prescribed atomic density. Using a simplified dipole-dipole interaction potential, we show that the atomic energy bands are very sensitive to the mean atomic density, even in a parameter regime where temperature and band populations exhibit only a very small density dependence. Bright lattices show energy shifts towards smaller band separations, while the effect is in the opposite direction and smaller for dark lattices. In general, dipole-dipole interaction strongly dominates the influence of quantum statistics, except for very large detunings, where the spontaneous emission rate is very small.

DOI: 10.1103/physreva.60.r2653

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