Correlation, excitation, and relaxation of the antiferromagnetic nanoparticle

J. D. Lee

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Correlation, excitation, and relaxation of the antiferromagnetic nanoparticle

J. D. Lee

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Abstract

We study the dynamics of spins in the canted antiferromagnetic hematite nanoparticles $α$-Fe$_2$O$_3$. The system includes an antiferromagnetic exchange ($J$) between two sublattices as well as the potential dominated by a uniaxial anisotropy and dissipates through the thermally triggered spin-phonon mechanism. The exchange $J$ is found to reduce the superparamagnetic relaxation and drive the incoherent relaxation of transverse spins in the low temperature. Dynamical properties are semi-quantitatively understood within a role of the exchange interaction $J$ and agree well with recent inelastic neutron scattering experiments.

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J. D. Lee. 2004-01-14. Correlation, excitation, and relaxation of the antiferromagnetic nanoparticle. https://arxiv.org/abs/cond-mat/0401247

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