Title :
Dynamics of thermally activated reversal in nonuniformly magnetized single particles
Author :
Boerner, Eric D. ; Bertram, H. Neal
Author_Institution :
Center for Magnetic Recording Res., California Univ., San Diego, La Jolla, CA, USA
fDate :
9/1/1997 12:00:00 AM
Abstract :
The dynamics of thermally activated reversal in elongated ferromagnetic particles is studied. A micromagnetic model is used which accounts for thermal fluctuations through the addition of a stochastic fluctuation field. Results are given approximating a particle of 5:1 aspect ratio, with exchange length equal to particle radius, which is typical of current particulate media. Fast relaxation of the magnetization is observed. Thermal effective volumes inferred from our results can be significantly less than particle volumes
Keywords :
coercive force; magnetic particles; magnetic recording; magnetisation reversal; aspect ratio; current particulate media; exchange length; micromagnetic model; nonuniformly magnetized single particles; particle radius; relaxation; stochastic fluctuation field; thermal effective volumes; thermal fluctuations; thermally activated reversal; Atmospheric modeling; Couplings; Equations; Fluctuations; Magnetization; Magnetostatic waves; Micromagnetics; Nearest neighbor searches; Stochastic processes; Stochastic resonance; Switches; Temperature; White noise;
Journal_Title :
Magnetics, IEEE Transactions on
