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arXiv · 0903.4234

Cold-atoms on a two-dimensional square optical lattice with an alternating potential

Huaiming Guo·Yuchuan Wen·Shiping Feng
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Abstract

The cold-atom on a two-dimensional square optical lattice is studied within the hard-core boson Hubbard model with an alternating potential. In terms of the quantum Monte Carlo method, it is shown explicitly that a supersolid phase emerges due to the presence of the alternating potential. For the weak alternating potential, the supersolid state appears for the whole range of hard-core boson densities except the half-filling case, where the system is a Mott insulator. However, for the strong alternating potential, besides the supersolid and Mott insulating states, a charge density wave phase appears.

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Huaiming Guo, Yuchuan Wen, Shiping Feng. 2009-03-25. Cold-atoms on a two-dimensional square optical lattice with an alternating potential. https://doi.org/10.1103/physreva.79.035401

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