Magnetization dynamics at elevated temperatures

Lei Xu; Shufeng Zhang

doi:10.1016/j.physe.2012.07.010

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arXiv · 1205.6506

Magnetization dynamics at elevated temperatures

Lei Xu·Shufeng Zhang

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Abstract

By using the quantum kinetic approach with the instantaneous local equilibrium approximation, we propose an equation that is capable of addressing magnetization dynamics for a wide range of temperatures. The equation reduces to the Landau-Lifshitz equation at low temperatures and to the paramagnetic Bloch equation at high temperatures. Near the Curie temperature, the magnetization reversal and dynamics depend on both transverse and longitudinal relaxations. We further include the stochastic fields in the dynamic equation in order to take into account fluctuation at high temperatures. Our proposed equation may be broadly used for modeling laser pump-probe experiments and heat assisted magnetic recording.

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Lei Xu, Shufeng Zhang. 2012-05-29. Magnetization dynamics at elevated temperatures. https://doi.org/10.1016/j.physe.2012.07.010

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