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arXiv · cond-mat/0307256

Tunable Magnetic Relaxation In Magnetic Nanoparticles

Xavier Waintal·Piet W. Brouwer
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Abstract

We investigate the magnetization dynamics of a conducting magnetic nanoparticle weakly coupled to source and drain electrodes, under the assumption that all relaxation comes from exchange of electrons with the electrodes. The magnetization dynamics is characterized by a relaxation time $t_1$, which strongly depends on temperature, bias voltage, and gate voltage. While a direct measure of a nanoparticle magnetization might be difficult, we find that $t_1$ can be determined through a time resolved transport measurement. For a suitable choice of gate voltage and bias voltage, the magnetization performs a bias-driven Brownian motion regardless of the presence of anisotropy.

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Xavier Waintal, Piet W. Brouwer. 2003-07-10. Tunable Magnetic Relaxation In Magnetic Nanoparticles. https://doi.org/10.1103/physrevlett.91.247201

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