Magnon Interference Tunneling Spectroscopy as a Probe of 2D Magnetism

TL;DR

This paper proposes a novel tunneling spectroscopy method using magnetic impurities to probe magnon dispersion and topological properties in 2D quantum magnets, including frustrated and Chern magnon bands.

Contribution

It introduces a new spectroscopic technique leveraging impurity-induced interference to study magnon properties in 2D magnets, including frustrated and topological phases.

Findings

Technique can determine magnon dispersion relations in 2D magnets.

Method can identify surface states in Chern magnon bands.

Applicable to frustrated magnetic systems with complex spin textures.

Abstract

Probing two-dimensional single-layer quantum magnets remains a significant challenge. In this letter, we propose exploiting tunneling spectroscopy in the presence of magnetic impurities to obtain information about the magnon dispersion relations in analogy to quasiparticle interference in non-magnetic materials. We show this technique can be used to establish the dispersion relations even for frustrated magnets, where the presence of an impurity generally leads to a nontrivial spin texture. Finally, we consider the problem of establishing Chern magnon bands in 2D magnets showing how tuneable impurities allow probing the nature of the surface states.