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arXiv · 1606.04297

Haldane insulator protected by reflection symmetry in the doped Hubbard model on the three-legged ladder

H. L. Nourse·I. P. McCulloch·C. Janani·B. J. Powell
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Abstract

We demonstrate the existence of an insulating phase in the three-legged Hubbard ladder at two-thirds filling. In this phase chargons are bound because the physics within a unit cell favors the formation of triplets. The resultant moments lead to a ground state in the Haldane phase, a symmetry protected topological state of matter. In this purely fermionic model, reflection is protecting but time reversal and dihedral symmetries are not, in contrast to spin models.

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H. L. Nourse, I. P. McCulloch, C. Janani, B. J. Powell. 2016-06-14. Haldane insulator protected by reflection symmetry in the doped Hubbard model on the three-legged ladder. https://doi.org/10.1103/physrevb.94.214418

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