Tunable Weyl fermions and Fermi arcs in magnetized topological crystalline insulators

TL;DR

This paper predicts that magnetically-doped topological crystalline insulators can host tunable Weyl semimetals with well-separated Weyl points and Fermi arcs, controllable via various external parameters, enabling potential applications in electronic devices.

Contribution

It demonstrates the realization of tunable Weyl semimetals in magnetically-doped topological crystalline insulators using $k ext{-}p$ and tight-binding calculations.

Findings

Weyl points are well separated and nearly degenerate in energy.

Weyl points and Fermi arcs are highly tunable by composition, pressure, magnetization, and other factors.

Potential for manipulating Weyl points and Fermi arcs for device applications.

Abstract

Based on $k\cdot p$ analysis and realistic tight-binding calculations, we find that time-reversal-breaking Weyl semimetals can be realized in magnetically-doped (Mn, Eu, Cr etc.) Sn$_{1-x}$Pb$_x$(Te,Se) class of topological crystalline insulators. All the Weyl points are well separated in momentum space and possess nearly the same energy due to high crystalline symmetry. Moreover, both the Weyl points and Fermi arcs are highly tunable by varying Pb/Sn composition, pressure, magnetization, temperature, surface potential etc., opening up the possibility of manipulating Weyl points and rewiring the Fermi arcs.