Magnetization reversal via internal spin waves in magnetic nanoparticles
Abstract
By numerically solving the equations of motion for atomic spins we show that internal spin-wave processes in large enough magnetic particles, initially in unstable states, lead to complete magnetization reversal and thermalization. The particle's magnetization strongly decreases in the middle of reversal and then recovers. We identify two main scenarios, exponential and linear spin-wave instabilities. For the latter, the longitudinal and transverse relaxation rates have been obtained analytically. Orientation dependence of these rates leads to a nonexponential relaxation of the particle's magnetization at long times.
Cite
@article{arxiv.0902.1492,
title = {Magnetization reversal via internal spin waves in magnetic nanoparticles},
author = {D. A. Garanin and H. Kachkachi},
journal= {arXiv preprint arXiv:0902.1492},
year = {2012}
}
Comments
14 PR pages, 5 figure captions, submitted to PRB. All figures are oversize and do not fit into this archive. Please, get the full version from http://www.lehman.edu/faculty/dgaranin/Intrinsic_relaxation.pdf