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arXiv · 1505.06958

Exotic Haldane Superfluid Phase of Soft-Core Bosons in Optical Lattices

Jian-Ping Lv·Z. D. Wang
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Abstract

We propose to realize an exotic Haldane superfluid (HSF) phase in an extended Bose-Hubbard model on the two-leg ladder (i.e., a two-species mixture of interacting bosons). The proposal is confirmed by means of large-scale quantum Monte Carlo simulations, with a significant part of the ground-state phase diagram being revealed. Most remarkably, the newly discovered HSF phase features both superfluidity and the non-local topological Haldane order. The effects induced by varying the number of legs are furthermore explored. Our results shed light on how topological superfluid emerges in bosonic systems.

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Jian-Ping Lv, Z. D. Wang. 2016-05-03. Exotic Haldane Superfluid Phase of Soft-Core Bosons in Optical Lattices. https://doi.org/10.1103/physrevb.93.174507

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