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arXiv · 1701.08828

Surfaces and Slabs of Fractional Topological Insulator Heterostructures

Sharmistha Sahoo·Alexander Sirota·Gil Young Cho·Jeffrey C. Y. Teo
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Abstract

Fractional topological insulators (FTI) are electronic topological phases in $(3+1)$ dimensions enriched by time reversal (TR) and charge $U(1)$ conservation symmetries. We focus on the simplest series of fermionic FTI, whose bulk quasiparticles consist of deconfined partons that carry fractional electric charges in integral units of $e^\ast=e/(2n+1)$ and couple to a discrete $\mathbb{Z}_{2n+1}$ gauge theory. We propose massive symmetry preserving or breaking FTI surface states. Combining the long-ranged entangled bulk with these topological surface states, we deduce the novel topological order of quasi-$(2+1)$ dimensional FTI slabs as well as their corresponding edge conformal field theories.

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Sharmistha Sahoo, Alexander Sirota, Gil Young Cho, Jeffrey C. Y. Teo. 2017-10-23. Surfaces and Slabs of Fractional Topological Insulator Heterostructures. https://doi.org/10.1103/physrevb.96.161108

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