Spin Nernst effect in the absence of a magnetic field

TL;DR

This paper investigates the spin Nernst effect in a mesoscopic device with Rashba spin-orbit interaction, revealing oscillatory behavior without peaks in the Seebeck coefficient and showing disorder can enhance the effect threefold.

Contribution

It demonstrates the occurrence of the spin Nernst effect without Seebeck peaks and shows disorder can significantly enhance this effect in a non-magnetic system.

Findings

Oscillatory spin Nernst effect occurs without Seebeck peaks.

Disorder can enhance the spin Nernst effect up to three times.

Counter propagating charge current due to interface effects in nonuniform systems.

Abstract

We study the spin Nernst effect of a mesoscopic four-terminal cross-bar device with the Rashba spin-orbit interaction (SOI) in the absence of a magnetic field. The interplay between the spin Nernst effect and the seebeck coefficient is investigated for a wide range of the Rashba SOI. When no peaks appeared in the seebeck coefficient, an oscillatory spin Nernst effect still occurs. In addition, the disorder effect on the spin Nernst effect is also studied. We find that the spin Nernst effect can be enhanced up to threefold by disorder. Besides, due to the interface effect, the counter propagating of the charge current to the direction of the temperature gradient is possible for a nonuniform system.