Thermo-magneto-electric transport through a torsion dislocation in a type I Weyl Semimetal

TL;DR

This paper investigates how torsional dislocations and magnetic fields influence electronic and thermoelectric transport in Weyl semimetals, revealing valley polarization and enhanced thermoelectric efficiency.

Contribution

It introduces a model combining torsional strain and magnetic field effects to analyze transport in Weyl semimetals with dislocations, highlighting novel chiral and thermoelectric phenomena.

Findings

Electric current shows chiral valley polarization.

Conductance exhibits Landau level signatures.

High thermopower and figure of merit predicted.

Abstract

We study electronic and thermoelectric transport in a type I Weyl semimetal nanojunction, with a torsional dislocation defect, in the presence of an external magnetic field parallel to the dislocation axis. The defect is modeled in a cylindrical geometry, as a combination of a gauge field accounting for torsional strain, and a delta-potential barrier for the lattice mismatch effect. In the Landauer formalism, we find that due to the combination of strain and magnetic field, the electric current exhibits chiral valley-polarization, and the conductance displays the signature of Landau levels. We also compute the thermal transport coefficients, where a high thermopower and a large figure of merit are predicted for the junction.