Thermoelectric effect of multiferroic oxide interfaces

TL;DR

This study explores the thermoelectric properties of electrons at multiferroic oxide interfaces, revealing controllable conductivities and thermopower sign changes due to magnetoelectric effects and carrier density tuning.

Contribution

It demonstrates electrical control over thermoelectric properties at multiferroic oxide interfaces, highlighting the influence of spin spiral helicity and electrostatic tuning.

Findings

No spin Hall current from temperature gradient

Presence of Seebeck effect at the interface

Thermopower sign change with carrier density tuning

Abstract

We investigate the thermoelectric properties of electrons at the interface of oxide heterostructure and in the presence of a multiferroic oxide with spiral spin order. We find there is no (spin) Hall current generated by the temperature gradient. A Seebeck effect is however present. Due to the magnetoelectric coupling, the charge and thermal conductivities are electrically controllable via the spin spiral helicity. Moreover, the thermopower exhibits a sign change when tuning electro-statically the carrier density.