Klein tunneling in Weyl semimetals under the influence of magnetic field

TL;DR

This paper explores Klein tunneling in Weyl semimetals under magnetic fields, revealing resonance conditions for perfect electron transmission and potential applications in electron filtering and electro-optic devices.

Contribution

It introduces the concept of resonance-induced perfect transmission rings in Weyl semimetals influenced by magnetic fields, extending Klein tunneling understanding to three-dimensional topological materials.

Findings

Resonance of Fermi wave vector leads to perfect transmission rings.

Magnetic field shifts transmission profiles enabling electron filtering.

Potential for highly selective electron transmission in Weyl semimetals.

Abstract

Klein tunneling refers to the absence of normal backscattering of electrons even under the case of high potential barriers. At the barrier interface, the perfect matching of electron and hole wavefunctions enables a unit transmission probability for normally incident electrons. It is theoretically and experimentally well understood in two-dimensional relativistic materials such as graphene. Here we investigate the Klein tunneling effect in Weyl semimetals under the influence of magnetic field induced by anti-symmetric ferromagnetic stripes placed at barrier boundaries. Our results show that the resonance of Fermi wave vector at specific barrier lengths gives rise to perfect transmission rings, i.e., three-dimensional analogue of the so-called magic transmission angles in two-dimensional Dirac semimetals. Besides, the transmission profile can be shifted by application of magnetic field, a property which may be utilized in electro-optic applications. When the applied potential is close to the Fermi level, a particular incident vector can be selected for transmission by tuning the applied magnetic field, thus enabling highly selective transmission of electrons in the bulk of Weyl semimetals. Our analytical and numerical calculations obtained by considering Dirac electrons in three regions and using experimentally feasible parameters can pave the way for relativistic tunneling applications in Weyl semimetals.