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arXiv · 1409.1234

Interaction Enabled Topological Crystalline Phases

Matthew F. Lapa·Jeffrey C. Y. Teo·Taylor L. Hughes
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Abstract

In this article we provide a general mechanism for generating interaction-enabled fermionic topological phases. We illustrate the mechanism with crystalline symmetry-protected topological phases in 1D and 2D. These non-trivial phases require interactions for their existence and, in the cases we consider, the free-fermion classification yields only a trivial phase. Similar to the interpretation of the Kitaev Majorana wire as a mean-field p-wave superconductor Hamiltonian arising from an interacting model with quartic interactions, we show that our systems can be interpreted as "mean-field" charge-$4e$ superconductors arising, e.g., from an interacting model with eight-body interactions, or through another physical mechanism. The quartet superconducting nature allows for the teleportation of full Cooper pairs, and in 2D for interesting semiclassical crystalline defects with non-Abelian anyon boundstates.

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Matthew F. Lapa, Jeffrey C. Y. Teo, Taylor L. Hughes. 2014-09-03. Interaction Enabled Topological Crystalline Phases. https://doi.org/10.1103/physrevb.93.115131

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