Thermoelectric transport of multi-Weyl semimetals in the quantum limit

Abstract

The thermoelectric transport properties of a three-dimensional multi-Weyl semimetal in the quantum limit are studied. In the calculation, we consider the different effects of the Gaussian and screened Coulomb electron-impurity scatterings. When the magnetic field is parallel to the electric field or the temperature gradient, the magnetoresistivity is always negative, but the thermopower strongly depends on the scattering potentials and the monopole charge. In the perpendicular field configuration, the situation becomes complicated. For the low electron density case, the increasing magnetic field makes the longitudinal conductivity comparable to the Hall one, which breaks the continuous growth of the Seebeck and Nernst responses, especially for the large monopole charge one. The thermoelectric Hall conductivity still indicates a plateau feature, but its value is multiplied by the monopole charge. Whether the longitudinal thermoelectric conductivity increases with the field depends on the potential type. This may be used to unveil the scattering mechanism in multi-Weyl semimetals.