A spincaloritronic battery

TL;DR

This paper analyzes a topological spin caloritronic device that converts temperature differences into electrical power, revealing how device geometry and material properties influence performance and suggesting new optimization strategies.

Contribution

It introduces a novel topological energy converter based on spin effects, providing analytical expressions and highlighting the impact of low electrical conductivity on efficiency.

Findings

Output voltage and ZT can be tuned by device geometry and material properties.

Low electrical conductivity may enhance the figure-of-merit (ZT).

The device offers a new approach to thermoelectric energy conversion.

Abstract

The thermoelectric performance of a topological energy converter is analyzed. The H-shaped device is based on a combination of transverse topological effects involving the spin: the inverse spin Hall effect and the spin Nernst effect. The device can convert a temperature drop in one arm into an electric power output in the other arm. Analytical expressions for the output voltage, the figure-of-merit (ZT) and energy converting efficiency are reported. We show that the output voltage and the ZT can be tuned by the geometry of the device and the physical properties of the material. Importantly, contrary to a conventional thermoelectric device, here a low electric conductivity may in fact enhance the ZT value, thereby opening a path to new strategies in optimizing the figure-of-merit.