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arXiv · 1407.0582

Stability of Topological Insulators with Non-Abelian Edge Excitations

Andrea Cappelli·Enrico Randellini
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Abstract

Chiral-antichiral pairs of non-Abelian Hall states, like the Pfaffian, Read-Rezayi and NASS states, can be used to model two-dimensional time-reversal invariant topological insulators. Their stability was shown to be associated to the presence of a Z_2 anomaly and characterized by the same Z_2 index introduced for free fermion and Abelian systems. In this work, we continue the stability analysis by providing the form of time-reversal invariant interactions that gap the non-Abelian edge excitations. Our approach is based on the description of non-Abelian states as projections of corresponding "parent" Abelian states.

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Andrea Cappelli, Enrico Randellini. 2014-07-02. Stability of Topological Insulators with Non-Abelian Edge Excitations. https://doi.org/10.1088/1751-8113/48/10/105404

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