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arXiv · 1907.07695

An exactly soluble model for a fractionalized Weyl semimetal

Fabian Hotz·Apoorv Tiwari·Oguz Turker·Tobias Meng·Ady Stern·Maciej Koch-Janusz·Titus Neupert
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Abstract

We construct an exactly solvable lattice model of a fractional Weyl semimetal (FWS). The low energy theory of this strongly interacting state is that of a Weyl semimetal built out of fractionally charged fermions. We show the existence of a universally quantized and fractional circular photogalvanic effect (CPGE) and a violation of the Wiedemann-Franz law in the system. Together with a spectral gap in the single-particle electronic Green's function they provide strong experimental signatures for this exotic gapless state of matter.

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Fabian Hotz, Apoorv Tiwari, Oguz Turker, Tobias Meng, Ady Stern, Maciej Koch-Janusz, Titus Neupert. 2019-07-17. An exactly soluble model for a fractionalized Weyl semimetal. https://doi.org/10.1103/physrevresearch.1.033029

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