Distribution of switching fields in magnetic granular materials

TY - JOUR

T1 - Distribution of switching fields in magnetic granular materials

AU - Hovorka, O.

AU - Pressesky, J.

AU - Ju, G.

AU - Berger, A.

AU - Chantrell, R.W.

PY - 2012/10/29

Y1 - 2012/10/29

N2 - We present analytical calculations and kinetic Monte-Carlo modeling of rate-dependent behavior of switching field distributions (SFDs) in an ensemble of Stoner-Wohfarth particles, assuming distributions of anisotropies and volumes, and thermal activation included by the Néel-Brown theory. By applying probabilistic arguments, we show that the SFD can be self-consistently separated into the contribution from distributions of intrinsic properties of particles and the (irreducible) contribution resulting solely from thermal fluctuations, which is shown to become a significant effect at sweep rates relevant to the recording process. This provides a unifying framework for systematic analysis of different classes of systems.

AB - We present analytical calculations and kinetic Monte-Carlo modeling of rate-dependent behavior of switching field distributions (SFDs) in an ensemble of Stoner-Wohfarth particles, assuming distributions of anisotropies and volumes, and thermal activation included by the Néel-Brown theory. By applying probabilistic arguments, we show that the SFD can be self-consistently separated into the contribution from distributions of intrinsic properties of particles and the (irreducible) contribution resulting solely from thermal fluctuations, which is shown to become a significant effect at sweep rates relevant to the recording process. This provides a unifying framework for systematic analysis of different classes of systems.

UR - http://www.scopus.com/inward/record.url?scp=84868667118&partnerID=8YFLogxK

U2 - 10.1063/1.4765085

DO - 10.1063/1.4765085

M3 - Article

AN - SCOPUS:84868667118

SN - 0003-6951

VL - 101

JO - Applied Physics Letters

JF - Applied Physics Letters

IS - 18

M1 - 182405

ER -