Conductance modulation in Weyl semimetals with tilted energy dispersion without a band gap

TL;DR

This paper explores how tilted energy dispersion in Weyl semimetals can create a conductance gap without a band gap, using electric and magnetic barriers, potentially enabling transistor applications.

Contribution

It introduces a novel mechanism for conductance gap formation in Weyl semimetals with tilted dispersion, involving pseudo-magnetic fields and realistic barrier structures.

Findings

Large conductance gap can be achieved without a band gap.

Tilted energy dispersion causes wave-vector shifts at barriers.

Temperature effects on tunneling conductance are analyzed.

Abstract

We investigate the tunneling conductance of Weyl semimetal with tilted energy dispersion by considering electron transmission through a p-n-p junction with one-dimensional electric and magnetic barrier. In the presence of both electric and magnetic barriers, we found that a large conductance gap can be produced by the aid of tilted energy dispersion without a band gap. The origin of this effect is the shift of the electrons wave-vector at barrier boundaries caused by i) the pseudo-magnetic field induced by electrical potential, i.e., a newly discovered feature that is only possible in the materials possessing tilted energy dispersion, ii) the real magnetic field induced by ferromagnetic layer deposited on the top of the system. We use realistic barrier structure applicable in current nanotechnology and analyze the temperature dependence of the tunneling conductance. The new approach presented here may resolve a major problem of possible transistor applications in topological semimetals, i.e., the absence of normal backscattering and gapless band structure.