# Making the Dzyaloshinskii-Moriya interaction visible

## TL;DR

This paper demonstrates how the visibility of magnons in Brillouin light spectroscopy depends on substrate thickness and provides guidelines to optimize substrate properties for better measurement of the Dzyaloshinskii-Moriya interaction in thin films.

## Contribution

It introduces a method to enhance magnon visibility by adjusting substrate properties, supported by analytical and numerical modeling.

## Key findings

- Magnon visibility depends strongly on dielectric seed thickness.
- Optimizing substrate properties improves measurement reliability.
- Guidelines for substrate selection to maximize signal.

## Abstract

Brillouin light spectroscopy is a powerful and robust technique for measuring the interfacial Dzyaloshinskii-Moriya interaction in thin films with broken inversion symmetry. Here we show that the magnon visibility, i.e. the intensity of the inelastically scattered light, strongly depends on the thickness of the dielectric seed material - SiO$_2$. By using both, analytical thin-film optics and numerical calculations, we reproduce the experimental data. We therefore provide a guideline for the maximization of the signal by adapting the substrate properties to the geometry of the measurement. Such a boost-up of the signal eases the magnon visualization in ultrathin magnetic films, speeds-up the measurement and increases the reliability of the data.