Dipole-dipole instability of atom clouds in a far-detuned optical dipole trap

D. Nagy; P. Domokos

doi:10.1103/physreva.75.053416

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Dipole-dipole instability of atom clouds in a far-detuned optical dipole trap

D. Nagy·P. Domokos

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Abstract

The effect of the dipole-dipole interaction on the far-off-resonance optical dipole trapping scheme is calculated by a mean-field approach. The trapping laser field polarizes the atoms and the accompanying dipole-dipole energy shift deepens the attractive potential minimum in a pancake-shaped cloud. At high density the thermal motion cannot stabilize the gas against self-contraction and an instability occurs. We calculate the boundary of the stable and unstable equilibrium regions on a two-dimensional phase diagram of the atom number and the ratio of the trap depth to the temperature. We discuss the limitations imposed by the dipole-dipole instability on the parameters needed to reach Bose-Einstein condensation in an optical dipole trap.

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BibTeX RIS

D. Nagy, P. Domokos. 2007-03-06. Dipole-dipole instability of atom clouds in a far-detuned optical dipole trap. https://doi.org/10.1103/physreva.75.053416

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