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

Volume

33

Issue

5

fYear

1997

fDate

9/1/1997 12:00:00 AM

Firstpage

3052

Lastpage

3054

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;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.617841

Filename

617841