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Supersolid Order from Disorder: Hard-Core Bosons on the Triangular Lattice

R. G. Melko·A. Paramekanti·A. A. Burkov·A. Vishwanath·D. N. Sheng·L. Balents
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Abstract

We study the interplay of Mott localization, geometric frustration, and superfluidity for hard-core bosons with nearest-neighbor repulsion on the triangular lattice. For this model at half-filling, we demonstrate that superfluidity survives for arbitrarily large repulsion, and that diagonal solid order emerges in the strongly correlated regime from an order-by-disorder mechanism. This is thus an unusual example of a stable supersolid phase of hard-core lattice bosons at a commensurate filling.

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R. G. Melko, A. Paramekanti, A. A. Burkov, A. Vishwanath, D. N. Sheng, L. Balents. 2005-07-14. Supersolid Order from Disorder: Hard-Core Bosons on the Triangular Lattice. https://doi.org/10.1103/physrevlett.95.127207

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