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arXiv · 1710.10103

Competing orders in the Hofstadter t-J model

Wei-Lin Tu·Frank Schindler·Titus Neupert·Didier Poilblanc
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Abstract

The Hofstadter model describes non-interacting fermions on a lattice in the presence of an external magnetic field. Motivated by the plethora of solid-state phases emerging from electron interactions, we consider an interacting version of the Hofstadter model including a Hubbard repulsion U. We investigate this model in the large-U limit corresponding to a t-J Hamiltonian with an external (orbital) magnetic field. By using renormalized mean field theory supplemented by exact diagonalization calculations of small clusters, we find evidence for competing symmetry-breaking phases, exhibiting (possibly co-existing) charge, bond and superconducting orders. Topological properties of the states are also investigated and some of our results are compared to related experiments involving ultra-cold atoms loaded on optical lattices in the presence of a synthetic gauge field.

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Wei-Lin Tu, Frank Schindler, Titus Neupert, Didier Poilblanc. 2019-12-18. Competing orders in the Hofstadter t-J model. https://doi.org/10.1103/physrevb.97.035154

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