# An exactly soluble model for a fractionalized Weyl semimetal

## TL;DR

This paper introduces an exactly solvable lattice model for a fractional Weyl semimetal, revealing unique experimental signatures like fractional CPGE and Wiedemann-Franz law violation, advancing understanding of strongly interacting topological states.

## Contribution

It presents the first exactly solvable model of a fractional Weyl semimetal with distinctive experimental signatures.

## Key findings

- Quantized fractional circular photogalvanic effect (CPGE)
- Violation of Wiedemann-Franz law
- Spectral gap in single-particle Green's function

## 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.