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arXiv · 1612.05212

Three-dimensional Topological Insulators and Bosonization

Andrea Cappelli·Enrico Randellini·Jacopo Sisti
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Abstract

Massless excitations at the surface of three-dimensional time-reversal invariant topological insulators possess both fermionic and bosonic descriptions, originating from band theory and hydrodynamic BF gauge theory, respectively. We analyze the corresponding field theories of the Dirac fermion and compactified boson and compute their partition functions on the three-dimensional torus geometry. We then find some non-dynamic exact properties of bosonization in (2+1) dimensions, regarding fermion parity and spin sectors. Using these results, we extend the Fu-Kane-Mele stability argument to fractional topological insulators in three dimensions.

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Andrea Cappelli, Enrico Randellini, Jacopo Sisti. 2016-12-15. Three-dimensional Topological Insulators and Bosonization. https://doi.org/10.1007/jhep05(2017)135

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