Weyl semimetal engineering by symmetry control in NiTe$_2$

TL;DR

This study demonstrates how symmetry control in NiTe2 can induce multiple Weyl points, revealing new pathways for engineering Weyl semimetals with potential applications in Weyltronics.

Contribution

The paper introduces a method to generate and manipulate multiple Weyl points in NiTe2 through symmetry breaking, expanding the understanding of topological phase engineering.

Findings

Three sets of Weyl points identified under symmetry breaking.

Weyl points originate from Dirac semimetal and additional crossings.

Fermi arcs confirm the topological nature of the Weyl semimetal.

Abstract

In this work, we investigate the emergence of Weyl points in an inversion symmetry-breaking 1T-NiTe$_2$ system. Through first-principles calculations based on the density functional theory combined with tight-binding methods, we find three distinct sets of Weyl crossings under an appropriate symmetry breaking. The first set, composed of four Weyl points, emerges from the Dirac semimetal. Surprisingly, the other two sets result in additional twenty-four Weyl crossings, depending on the weight of the symmetry breaking. We investigate the topological characteristics of the Weyl semimetals by computing the Weyl chirality, Berry curvature, and the evolution of Wannier charge centers. Additionally, the bulk-boundary correspondence has been shown by computing the Fermi arcs. Our results provide a way for creating and manipulating distinct sets of Weyl points with appropriate external control, which can be valuable for applications in Weyltronics.