Non-Abelian topological insulators from an array of quantum wires

Eran Sagi; Yuval Oreg

doi:10.1103/physrevb.90.201102

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arXiv · 1403.1791

Non-Abelian topological insulators from an array of quantum wires

Eran Sagi·Yuval Oreg

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Abstract

We suggest a construction of a large class of topological states using an array of quantum wires. First, we show how to construct a Chern insulator using an array of alternating wires that contain electrons and holes, correlated with an alternating magnetic field. This is supported by semi-classical arguments and a full quantum mechanical treatment of an analogous tight-binding model. We then show how electron-electron interactions can stabilize fractional Chern insulators (Abelian and non-Abelian). In particular, we construct a relatively stable non-Abelian $\mathbb{Z}_{3}$ parafermion state. Our construction is generalized to wires with alternating spin-orbit couplings, which give rise to integer and fractional (Abelian and non-Abelian) topological insulators. The states we construct are effectively two-dimensional, and are therefore less sensitive to disorder than one-dimensional systems. The possibility of experimental realization of our construction is addressed.

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Eran Sagi, Yuval Oreg. 2014-03-07. Non-Abelian topological insulators from an array of quantum wires. https://doi.org/10.1103/physrevb.90.201102

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