Splitting the Topological Degeneracy of non-Abelian Anyons

Parsa Bonderson

doi:10.1103/physrevlett.103.110403

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arXiv · 0905.2726

Splitting the Topological Degeneracy of non-Abelian Anyons

Parsa Bonderson

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Abstract

We examine tunneling of topological charge between non-Abelian anyons as a perturbation of the long-range effective theory of a topologically ordered system. We obtain energy corrections in terms of the anyons' universal algebraic structure and non-universal tunneling amplitudes. We find that generic tunneling completely lifts the topological degeneracy of non-Abelian anyons. This degeneracy splitting is exponentially suppressed for long distances between anyons, but leaves no topological protection at shorter distances. We also show that general interactions of anyons can be expressed in terms of the transfer of topological charge, and thus can be treated effectively as tunneling interactions.

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Parsa Bonderson. 2009-05-17. Splitting the Topological Degeneracy of non-Abelian Anyons. https://doi.org/10.1103/physrevlett.103.110403

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