Tunable magnon band topology and magnon orbital Nernst effect in noncollinear antiferromagnets

TL;DR

This paper theoretically explores how external magnetic fields induce topological phase transitions in noncollinear antiferromagnets, enabling tunable control of the magnon orbital Nernst effect with potential experimental implications.

Contribution

It introduces the concept of tunable magnon orbital Nernst effect via magnetic field-induced topological transitions in noncollinear antiferromagnets.

Findings

Magnetic field induces topological phase transitions in magnon bands.

Magnon orbital Nernst conductivity peaks near phase transition points.

The effect can be tuned by external magnetic fields.

Abstract

We theoretically investigate the intrinsic magnon orbital Nernst effect (ONE) in noncollinear antiferromagnets with Kagom\'e spin systems. Our analysis reveals that an externally applied magnetic field induces topological phase transitions in the magnonic system, characterized by the closing and reopening of the band gap between distinct magnon bands. These transitions enable tunable control of the magnon orbital Nernst effect with applied magnetic field, with a pronounced enhancement in magnon orbital Nernst conductivity near the phase transition points. This tunability presents a promising direction for experimental detection of the magnon ONE.