Article

Transition from a two-dimensional superfluid to a one-dimensional Mott insulator.

Department of Theoretical Physics, Royal Institute of Technology, AlbaNova, SE-106 91 Stockholm, Sweden.
Physical Review Letters (Impact Factor: 7.73). 10/2007; 99(11):110401. DOI: 10.1103/PHYSREVLETT.99.110401
Source: PubMed

ABSTRACT A two-dimensional system of atoms in an anisotropic optical lattice is studied theoretically. If the system is finite in one direction, it is shown to exhibit a transition between a two-dimensional superfluid and a one-dimensional Mott insulating chain of superfluid tubes. Monte Carlo simulations are consistent with the expectation that the phase transition is of Kosterlitz-Thouless type. The effect of the transition on experimental time-of-flight images is discussed.

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