Title :
Implementation of the "hyperdynamics of infrequent events" method for acceleration of thermal switching dynamics of magnetic moments
Author :
Chubykalo-Fesenko, Oksana A. ; Sanchez, Felipe Garcia ; Chantrell, Roy W.
Author_Institution :
Inst. de Ciencia de Mater. de Madrid, Spain
fDate :
7/1/2004 12:00:00 AM
Abstract :
For acceleration of the calculations of thermal magnetic switching, we report the use of the Voter method, recently proposed in chemical physics (also called "hyperdynamics of the infrequent events"). The method consists of modification of the magnetic potential so that the transition state remains unchanged. We have found that the method correctly describes the mean first passage time even in the case of small damping (precessional case) and for an oblique angle between the anisotropy and the field directions. Due to the costly evaluation of the lowest energy eigenvalue, the actual acceleration depends on its fast computation. In the current implementation, it is limited to intermediate time scale and to small system size.
Keywords :
computational electromagnetics; magnetic moments; magnetic recording; magnetic relaxation; magnetic switching; numerical analysis; spin dynamics; Voter method; anisotropy; chemical physics; computational magnetics; energy eigenvalue; field directions; infrequent events hyperdynamics; intermediate time scale; magnetic moments; magnetic potential modification; mean first passage time; numerical methods; relaxation; small damping; spin dynamics; thermal magnetic switching; thermal switching dynamics acceleration; transition state; Acceleration; Anisotropic magnetoresistance; Chemicals; Damping; Eigenvalues and eigenfunctions; Magnetic anisotropy; Magnetic moments; Magnetic switching; Perpendicular magnetic anisotropy; Physics; Computational magnetics; numerical methods; spin dynamics and relaxation;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2004.830397