# How to accurately determine a saturation magnetization of the sample in a ferromagnetic resonance experiment?

## TL;DR

This paper presents a method to accurately determine the saturation magnetization of magnetic samples using ferromagnetic resonance data, validated on historical and recent measurements across different materials.

## Contribution

It introduces a novel approach that relates resonance frequency and energy curvature to calculate saturation magnetization from FMR data, applicable to various magnetic materials.

## Key findings

- Magnetization values from FMR data match independent measurements.
- Method validated on bulk, thin film, and ultrathin magnetic samples.
- Provides a new tool for precise magnetic characterization.

## Abstract

The phenomenon of ferromagnetic resonance (FMR) is still being exploited for determining the magnetocrystalline anisotropy constants of magnetic materials. We show that one can also determine accurately the saturation magnetization of the sample using results of FMR experiments after taking into account the relationship between resonance frequency and curvature of the spatial distribution of free energy at resonance. Specifically, three examples are given of calculating saturation magnetization from FMR data: we use historical Bickford's measurements from 1950 for bulk magnetite, Liu's measurements from 2007 for a 500 mn thin film of a weak ferromagnet (Ga, Mn)As, and Wang's measurements from 2014 for an ultrathin film of YIG. In all three cases, the magnetization values we have determined are consistent with the results of measurements.