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arXiv · 0709.4258

Fractional statistics of topological defects in graphene and related structures

B. Seradjeh·M. Franz
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Abstract

We show that fractional charges bound to topological defects in the recently proposed time-reversal-invariant models on honeycomb and square lattices obey fractional statistics. The effective low-energy description is given in terms of a `doubled' level-2 Chern-Simons field theory, which is parity and time-reversal invariant and implies two species of semions (particles with statistical angle pi/2) labeled by a new emergent quantum number that we identify as the fermion axial charge.

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B. Seradjeh, M. Franz. 2007-09-26. Fractional statistics of topological defects in graphene and related structures. https://doi.org/10.1103/physrevlett.101.146401

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