
An Interacting Topological Crystalline Insulator  Bela Bauer (Microsoft)
 ABC Physics (Atomic/Bio/Condensed Matter) Special Seminar
Date: Wednesday, April 27, 2016 2:30 PM Location: PAT INT conference room
Abstract
Strongly correlated analogues of topological insulators have been explored in systems with purely onsite symmetries, such as timereversal or charge conservation. Here, we use recently developed tensor network tools to study a quantum state of interacting bosons which is featureless in the bulk, but distinguished from an atomic insulator in that it exhibits entanglement which is protected by its spatial symmetries. These properties are encoded in a model manybody wavefunction that describes a fully symmetric insulator of bosons on the honeycomb lattice at half filling per site. We demonstrate this by computing the boundary entanglement spectra, finding a gapless entanglement edge described by a conformal field theory as well as degeneracies protected by the nontrivial action of combined chargeconservation and spatial symmetries on the edge. Our results extend to a related insulating state of electrons, with shortranged entanglement and no band insulator analogue. 


