Interaction-induced anomalous quantum Hall state on the honeycomb lattice

by Tanja Duric (London Centre for Nanotechnology)

Wednesday 11 Feb 2015, 15:00 → 16:00 Europe/Rome

Aula Conversi (Dip. di Fisica - Edificio G. Marconi)

Interaction-induced anomalous quantum Hall state on the honeycomb lattice We examine the existence of the interaction-generated quantum anomalous Hall phase on the honeycomb lattice. We use the exact diagonalization method to study properties of small clusters with open boundary conditions, and contrary to previous studies, we find clear signatures of the topological phase transition for finite-size clusters. We also examine the applicability of the entangled-plaquette-state ansatz to describe the ground states of the system. Using the entangled-plaquette-state ansatz we study the ground-state properties of the system for larger system sizes and show that the results agree with the exact diagonalization results for small clusters. This confirms the validity of the entangled-plaquette-state ansatz to describe the ground states of the system and provides further confirmation of the existence of the quantum anomalous Hall phase in the thermodynamic limit.