Micromagnetic study of inertial spin waves in ferromagnetic nanodots
Abstract
Here we report the possibility to excite ultra-short spin waves in ferromagnetic thin-films by using time-harmonic electromagnetic fields with terahertz frequency. Such ultra-fast excitation requires to include inertial effects in the description of magnetization dynamics. In this respect, we consider the inertial Landau-Lifshitz-Gilbert (iLLG) equation and develop analytical theory for exchange-dominated inertial spin waves. The theory predicts a finite limit for inertial spin wave propagation velocity, as well as spin wave spatial decay and lifetime as function of material parameters. Then, guided by the theory, we perform numerical micromagnetic simulations that demonstrate the excitation of ultra-short inertial spin waves (20 nm long) propagating at finite speed in a confined magnetic nanodot. The results are in agreement with the theory and provide the order of magnitude of quantities observable in realistic ultra-fast dynamics experiments.
Keywords
Cite
@article{arxiv.2302.10759,
title = {Micromagnetic study of inertial spin waves in ferromagnetic nanodots},
author = {Massimiliano d'Aquino and Salvatore Perna and Matteo Pancaldi and Riccardo Hertel and Stefano Bonetti and Claudio Serpico},
journal= {arXiv preprint arXiv:2302.10759},
year = {2024}
}
Comments
The following article has been accepted by Physical Review B. After it is published, it will be found at https://journals.aps.org/prb/. Revised version, 9 pages, 6 figures. Changes made in v2: added some references, minor edits and corrections