Chirality Enables Thermal Magnon Transistors

TL;DR

This paper presents a theoretical study on how chirality in magnetic films enables control of thermal magnon currents, diverting a significant portion into a magnetic gate, which could be useful for heat management in magnonic circuits.

Contribution

It introduces a novel theory of chiral thermal spin pumping that allows control of magnon currents via magnetization orientation in magnetic films.

Findings

Chirality diverts up to 50% of magnon current into the gate.

Thermal spin pumping can be controlled by rotating magnetization.

Potential application in heat management for magnonic circuits.

Abstract

We report a theory of thermal spin pumping into proximity magnets under a transverse-bias-driven heat flow of magnons in magnetic films when the dipolar coupling to the magnetic gate is tuned to be "chiral". While there is no rectification of the magnon current in the film, we predict that chirality diverts a large percentage (50$\%$ for perfect chirality) of it into the gate. This transverse thermal spin pumping effect can be controlled by rotating the film magnetization and may help manage the heat flow in future magnonic circuits.