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Non-Abelian gauge potentials for ultra-cold atoms with degenerate dark states

J. Ruseckas·G. Juzeliunas·P. Oehberg·M. Fleischhauer
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Abstract

We show that the adiabatic motion of ultra-cold, multi-level atoms in spatially varying laser fields can give rise to effective non-Abelian gauge fields if degenerate adiabatic eigenstates of the atom-laser interaction exist. A pair of such degenerate dark states emerges e.g. if laser fields couple three internal states of an atom to a fourth common one under pairwise two--photon-resonance conditions. For this so-called tripod scheme we derive general conditions for truly non-Abelian gauge potentials and discuss special examples. In particular we show that using orthogonal laser beams with orbital angular momentum an effective magnetic field can be generated that has a monopole component.

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J. Ruseckas, G. Juzeliunas, P. Oehberg, M. Fleischhauer. 2005-03-08. Non-Abelian gauge potentials for ultra-cold atoms with degenerate dark states. https://doi.org/10.1103/physrevlett.95.010404

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