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arXiv · 0907.0423

Frustrated quantum antiferromagnetism with ultracold bosons in a triangular lattice

Andre Eckardt·Philipp Hauke·Parvis Soltan-Panahi·Christoph Becker·Klaus Sengstock·Maciej Lewenstein
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Abstract

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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Andre Eckardt, Philipp Hauke, Parvis Soltan-Panahi, Christoph Becker, Klaus Sengstock, Maciej Lewenstein. 2010-01-24. Frustrated quantum antiferromagnetism with ultracold bosons in a triangular lattice. https://doi.org/10.1209/0295-5075%2F89%2F10010

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