Volume 82, Number 1, April 2008
|Number of page(s)||6|
|Section||Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties|
|Published online||11 March 2008|
Magnetization reversal and nonexponential relaxation via instabilities of internal spin waves in nanomagnets
Physics Department, Lehman College, City University of New York - 250 Bedford Park Boulevard West, Bronx, New York 10468-1589, USA
2 Groupe d'Etude de la Matière Condensée, CNRS UMR8634, Université de Versailles St. Quentin 45 av. des Etats-Unis, 78035 Versailles, France, EU
Corresponding author: email@example.com
Accepted: 8 February 2008
A magnetic particle with atomic spins ordered in an unstable direction is an example of a false vacuum that decays via excitation of internal spin waves. Coupled evolution of the particle's magnetization (or the vacuum state) and spin waves, considered in the time-dependent vacuum frame, leads to a peculiar relaxation that is very fast at the beginning but slows down to a nonexponential long tail at the end. The two main scenarios are linear and exponential spin-wave instabilities. For the former, the longitudinal and transverse relaxation rates have been obtained analytically. Numerical simulations show that the particle's magnetization strongly decreases in the middle of reversal and then recovers.
PACS: 75.50.Tt – Fine particle systems; nanocrystalline materials / 75.10.Hk – Classical spin models / 75.30.Ds – Spin waves
© EPLA, 2008
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.