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Frustrated quantum antiferromagnetism with ultracold bosons in a triangular lattice

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 نشر من قبل Andre Eckardt
 تاريخ النشر 2009
  مجال البحث فيزياء
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We propose to realize the anisotropic triangular-lattice Bose-Hubbard model with positive tunneling matrix elements by using ultracold atoms in an optical lattice dressed by a fast lattice oscillation. This model exhibits frustrated antiferromagnetism at experimentally feasible temperatures; it interpolates between a classical rotor model for weak interaction, and a quantum spin-1/2 $XY$-model in the limit of hard-core bosons. This allows to explore experimentally gapped spin liquid phases predicted recently [Schmied et al., New J. Phys. {bf 10}, 045017 (2008)].



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