arXiv:1303.4455 · Physical Review Letters

Topological Entanglement Entropy with a Twist

Benjamin J. Brown, Stephen D. Bartlett, Andrew C. Doherty, S. D. Barrett

Published Nov 26, 2013• 46 citations

Abstract

Defects in topologically ordered models have interesting properties that are reminiscent of the anyonic excitations of the models themselves. For example, dislocations in the toric code model are known as twists and possess properties that are analogous to Ising anyons. We strengthen this analogy by using the topological entanglement entropy as a diagnostic tool to identify properties of both defects and excitations in the toric code. Specifically, we show, through explicit calculation, that the toric code model including twists and dyon excitations has the same quantum dimensions, the same total quantum dimension, and the same fusion rules as an Ising anyon model.

DOI: 10.1103/physrevlett.111.220402

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