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arXiv · 2107.10056

Interplay of interactions, disorder and topology in the Haldane-Hubbard model

Tian-Cheng Yi·Shijie Hu·Eduardo V. Castro·Rubem Mondaini
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Abstract

We investigate the ground-state phase diagram of the spinless Haldane-Hubbard model in the presence of quenched disorder, contrasting results obtained from both exact diagonalization as well as density matrix renormalization group, applied to a honeycomb cylinder. The interplay of disorder, interactions and topology gives rise to a rich phase diagram, and in particular highlights the possibility of a disorder-driven trivial-to-topological transition in the presence of finite interactions. That is, the topological Anderson insulator, demonstrated in non-interacting settings, is shown to be stable to the presence of sufficiently small interactions before a charge density wave Mott insulator sets in. We further perform a finite-size analysis of the transition to the ordered state in the presence of disorder, finding a mixed character of first and second order transitions in finite lattices, tied to specific conditions of disorder realizations and boundary conditions used.

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Tian-Cheng Yi, Shijie Hu, Eduardo V. Castro, Rubem Mondaini. 2021-11-22. Interplay of interactions, disorder and topology in the Haldane-Hubbard model. https://doi.org/10.1103/physrevb.104.195117

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