Emergence of Spinon Fermi Arcs in the Weyl-Mott Metal-Insulator Transition

TL;DR

This paper introduces a minimal model for the Weyl-Mott insulator transition, revealing spinon Fermi arcs and an intermediate bad semimetal phase, with distinctive surface gap features detectable by ARPES.

Contribution

It presents a new microscopic model capturing the WMI transition, highlighting surface spinon Fermi arcs and their experimental signatures.

Findings

Identification of spinon Fermi arcs on WMI surfaces

Discovery of an intermediate bad semimetal phase

Surface Mott gap suppression detectable by ARPES

Abstract

The Weyl-Mott insulator (WMI) has been postulated as a novel type of correlated insulator with non-trivial topological properties. We introduce a minimal microscopic model that captures generic features of the WMI transition in Weyl semimetals. The model hosts a bulk Mott insulator with spinon Fermi arcs on its surfaces which we identify as a WMI. At finite temperatures, we find an intermediate Weyl semimetallic phase with no quasiparticles which is consistent with the bad semimetallic behavior observed in pyrochlore iridates, A2Ir2O7, close to the Mott transition. Spinon Fermi arcs lead to a suppression of the bulk Mott gap at the surface of the WMI, in contrast to the gap enhancement found in conventional Mott insulators, which can be detected through angular resolved photoemission spectroscopy (ARPES).