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×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.
| Original language | English |
|---|---|
| Article number | 245115 |
| Journal | Physical Review B |
| Volume | 109 |
| Issue number | 24 |
| DOIs | |
| State | Published - Jun 15 2024 |
Funding
R.S., H.R., and A.D.M. acknowledge support from the US Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award No. DE-SC0022311. B.R. acknowledges support from the German Research Foundation under Grant RO 2247/11-1 and the hospitality of the University of Tennessee, where a portion of this work was performed. The US Department of Energy, Office of Science, National Quantum Information Science Research Centers, Quantum Science Center has supported G.A., who contributed to the DMRG aspects in this paper. R.S. acknowledges the Office of Information Technology (OIT) at the University of Tennessee for providing additional computational resources to carry out this project. The authors would like to thank F. Heidrich-Meisner, H. Barghathi, P. Laurell, and E. Dagotto for useful discussions.