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Spatial Coherence of a Strongly Interacting Bose Gas in the Trimerized Kagome Lattice

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 نشر من قبل Tsz Him Leung
 تاريخ النشر 2019
  مجال البحث فيزياء
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We produce a trimerized kagome lattice for ultracold atoms using an optical superlattice formed by overlaying triangular lattices generated with two colors of light at a 2:1 wavelength ratio. Adjusting the depth of each lattice tunes the strong intra-trimer (J) and weak inter-trimer (J) tunneling energies, and also the on-site interaction energy U. Two different trimerization patterns are distinguished using matter-wave diffraction. We characterize the coherence of a strongly interacting Bose gas in this lattice, observing persistent nearest-neighbor spatial coherence in the large U/J limit, and that such coherence displays asymmetry between the strongly and the weakly coupled bonds.

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