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Effects of the Magnetic Field on the Relaxation of Small Particle Systems

Oscar Iglesias·Amilcar Labarta
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Abstract

We study the effect of a magnetic field on the thermal relaxation of non-interacting small monodomain particle systems particles with a distribution of anisotropy constants and random easy-axes directions. Numerical calculations of the relaxation curves for different distribution widths, and under different magnetic fields $H$ and temperatures $T$, have been performed in the framework of a two-state approximation. We show how the obtained data can be analyzed in terms of an modified $Tln(t/τ_0)$ scaling from which the field dependence of the mean relaxing energy barriers can be extracted, a microscopic information which is not easily obtainable by other methods.

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Oscar Iglesias, Amilcar Labarta. 2002-05-30. Effects of the Magnetic Field on the Relaxation of Small Particle Systems. https://doi.org/10.1016/s0927-0256(02)00337-3

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