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arXiv · 1803.07255

Bosonic Haldane insulator in the presence of local disorder: A quantum Monte Carlo study

Jian-Ping Lv·Jian-Sheng Wang
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Abstract

The Haldane phase (HP) is a paradigmatic example of symmetry protected topological phase. We explore how the bosonic HP behaves in the presence of local disorder, employing quantum Monte Carlo simulations of an extended Bose-Hubbard model subject to uncorrelated, quenched disorders. We find that the HP is robust against a weak disorder and the non-local string order of HP exhibits a reentrant behavior. Besides, a direct transition between the HP and superfluid phase is uncovered. A significant part of the ground-state phase diagram is established for the model, unveiling the location of HP surrounded by Bose glass, charge density wave and superfluid phases. We also mention a possible experimental scheme with optical lattice emulator to realize the present findings.

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Jian-Ping Lv, Jian-Sheng Wang. 2018-03-20. Bosonic Haldane insulator in the presence of local disorder: A quantum Monte Carlo study. https://doi.org/10.1209/0295-5075/123/10004

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