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arXiv · 1806.01860

Composite Weyl semimetal as a parent state for three dimensional topologically ordered phases

Eran Sagi·Ady Stern·David F. Mross
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Abstract

We introduce (3+1) dimensional models of short-range-interacting electrons that form a strongly correlated many-body state whose low-energy excitations are relativistic neutral fermions coupled to an emergent gauge field, $\text{QED}_{4}$. We discuss the properties of this critical state and its instabilities towards exotic phases such as a gapless `composite' Weyl semimetal and fully gapped topologically ordered phases that feature anyonic point-like as well as line-like excitations. These fractionalized phases describe electronic insulators. They may be further enriched by symmetries which results in the formation of non-trivial surface states.

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Eran Sagi, Ady Stern, David F. Mross. 2018-06-05. Composite Weyl semimetal as a parent state for three dimensional topologically ordered phases. https://doi.org/10.1103/physrevb.98.201111

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