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arXiv · 1009.2991

Holographic fractional topological insulators in 2+1 and 1+1 dimensions

Andreas Karch·Joseph Maciejko·Tadashi Takayanagi
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Abstract

We give field theory descriptions of the time-reversal invariant quantum spin Hall insulator in 2+1 dimensions and the particle-hole symmetric insulator in 1+1 dimensions in terms of massive Dirac fermions. Integrating out the massive fermions we obtain a low-energy description in terms of a topological field theory, which is entirely determined by anomaly considerations. This description allows us to easily construct low-energy effective actions for the corresponding `fractional' topological insulators, potentially corresponding to new states of matter. We give a holographic realization of these fractional states in terms of a probe brane system, verifying that the expected topologically protected transport properties are robust even at strong coupling.

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Andreas Karch, Joseph Maciejko, Tadashi Takayanagi. 2010-11-09. Holographic fractional topological insulators in 2+1 and 1+1 dimensions. https://doi.org/10.1103/physrevd.82.126003

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