PT invariant Weyl semimetals in gauge symmetric systems

TL;DR

This paper demonstrates that Weyl semimetals can exist in systems with gauge potentials that preserve both time-reversal and inversion symmetries, expanding the understanding of topological phases in fermionic lattices.

Contribution

It introduces a cubic lattice model with $$-fluxes showing Weyl points under gauge symmetries, highlighting differences between physical and canonical symmetries, and analyzes robustness in experimental conditions.

Findings

Weyl semimetals can occur with preserved T and P symmetries in gauge systems.

Gauge potentials influence the formation of Weyl points.

Robustness of Weyl phases under trapping and flux perturbations was demonstrated.

Abstract

Weyl semimetals typically appear in systems in which either time-reversal (T) or inversion (P}) symmetry are broken. Here we show that in the presence of gauge potentials these topological states of matter can also arise in fermionic lattices preserving both T and P. We analyze in detail the case of a cubic lattice model with $\pi$-fluxes, discussing the role of gauge symmetries in the formation of Weyl points and the difference between the physical and the canonical T and P symmetries. Motivated by advances in ultracold atom experiments and by the possibility of using synthetic magnetic fields, we examine the robustness of the Weyl semimetal phase in the presence of trapping potentials and random perturbations of the magnetic fluxes, which can be compared to a local disorder in realistic scenarios.