# Spin Seebeck and Spin Nernst Effects of Magnons in Noncollinear Antiferromagnetic Insulators

## TL;DR

This study demonstrates that noncollinear antiferromagnetic insulators can efficiently generate magnon spin currents via spin Seebeck and spin Nernst effects, with quantitative predictions for potassium iron jarosite.

## Contribution

It provides a combined theoretical and computational analysis of heat-to-spin conversion in noncollinear antiferromagnetic insulators, highlighting their potential for spintronic applications.

## Key findings

- Predicted spin Seebeck conversion factor of 0.2 μV/K at 20 K.
- Explicit evaluation of spin Seebeck and Nernst effects in kagome lattice.
- Identification of noncollinear antiferromagnets as promising materials for magnon spin current generation.

## Abstract

Our joint theoretical and computer experimental study of heat-to-spin conversion reveals that noncollinear antiferromagnetic insulators are promising materials for generating magnon spin currents upon application of a temperature gradient: they exhibit spin Seebeck and spin Nernst effects. Using Kubo theory and spin dynamics simulations, we explicitly evaluate these effects in a single kagome sheet of potassium iron jarosite, KFe$_3$(OH)$_6$(SO$_4$)$_2$, and predict a spin Seebeck conversion factor of $0.2 \mu\mathrm{V}/\mathrm{K}$ at a temperature of $20 \mathrm{K}$.