Magnetocaloritronic nanomachines

TL;DR

This paper introduces a magnetocaloritronic circuit element utilizing domain wall motion, explores its potential for cooling and power generation, and discusses its efficiency and future prospects in magnetic insulators.

Contribution

It presents the concept of a magnetocaloritronic device based on domain walls, drawing analogies with Carnot machines and thermoelectric systems, and proposes a figure of merit for such devices.

Findings

Magnetocaloritronic figure of merit is small for transition-metal magnets.

Potential for higher efficiency in ferromagnetic insulators.

Analogies established between thermoelectric and magnetocaloritronic devices.

Abstract

We introduce and study a magnetocaloritronic circuit element based on a domain wall that can move under applied voltage, magnetic field and temperature gradient. We draw analogies between the Carnot machines and possible devices employing such circuit element. We further point out the parallels between the operational principles of thermoelectric and magnetocaloritronic cooling and power generation and also introduce a magnetocaloritronic figure of merit. Even though the magnetocaloritronic figure of merit turns out to be very small for transition-metal based magnets, we speculate that larger numbers may be expected in ferromagnetic insulators.