arXiv:1505.06958 · Physical review. B./Physical review. B
Exotic Haldane superfluid phase of soft-core bosons in optical lattices
Jian-Ping Lv, Z. D. Wang
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 nonlocal 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.