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arXiv · 2012.11461

Chiral Bosonic Topological Insulator on the Honeycomb Lattice with Anisotropic Interactions

Amrita Ghosh·Eytan Grosfeld
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Abstract

We study hard-core bosons on the honeycomb lattice in the presence of anisotropic nearest-neighbor repulsive interactions. Using a quantum Monte Carlo (QMC) technique, we extract the phase diagram of the model in terms of the filling and the anisotropy. At half-filling we find a dimer insulator phase near maximum anisotropy that is characterized by a finite topological entanglement entropy $\ln(2)/2$, indicative of a fractional quantum Hall state for bosons. We identify the presence of edge states and derive a QMC-based method to extract and verify their chirality. Remarkably, this phase arises in the absence of magnetic flux and without explicit lattice frustration.

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Amrita Ghosh, Eytan Grosfeld. 2020-12-21. Chiral Bosonic Topological Insulator on the Honeycomb Lattice with Anisotropic Interactions. https://doi.org/10.1103/physrevb.103.205118

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