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arXiv · 2310.17614

Topological and magnetic properties of the interacting Bernevig-Hughes-Zhang model

Rahul Soni·Harini Radhakrishnan·Bernd Rosenow·Gonzalo Alvarez·Adrian Del Maestro
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Abstract

We investigate the effects of electronic correlations on the Bernevig-Hughes-Zhang model using the real-space density matrix renormalization group (DMRG) algorithm. We introduce a method to probe topological phase transitions in systems with strong correlations using DMRG, substantiated by an unsupervised machine learning methodology that analyzes the orbital structure of the real-space edges. Including the full multi-orbital Hubbard interaction term, we construct a phase diagram as a function of a gap parameter ($m$) and the Hubbard interaction strength ($U$) via exact DMRG simulations on $N\times 4$ cylinders. Our analysis confirms that the topological phase persists in the presence of interactions, consistent with previous studies, but it also reveals an intriguing phase transition from a paramagnetic to a stripey antiferromagnetic topological insulator. The combination of the magnetic structure factor, strength of magnetic moments, and the orbitally resolved density, provides real-space information on both topology and magnetism in a strongly correlated system.

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Rahul Soni, Harini Radhakrishnan, Bernd Rosenow, Gonzalo Alvarez, Adrian Del Maestro. 2023-10-26. Topological and magnetic properties of the interacting Bernevig-Hughes-Zhang model. https://doi.org/10.1103/physrevb.109.245115

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