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arXiv · 0706.3661

Thermodynamic properties of magneto-anisotropic nanoparticles

Malay Bandyopadhyay
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Abstract

The purpose of this paper is to study the thermodynamic equilibrium properties of a collection of non-interacting three-dimensional (3D) magnetically anisotropic nanoparticles in the light of classical statistical physics. Pertaining to the angular dependence ($α$) of the magnetic field with the anisotropy axis, energy landscape plots are obtained which reveal a continuous transition from a double well to a single well for $α=\fracπ{2}$ and show asymmetric bistable shape for other values of $α$. The present analysis is related with the interpretation of equilibrium magnetization and static susceptibility of nanomagnetic system as a function of external magnetic field, $B$, and temperature, $T$. The magnetization and susceptibility confirms the non Langevin behaviour of magneto-anisotropic monodomain particles. The susceptibility analysis establishes the ferromagnetic, antiferromagnetic and paramagnetic like coupling for various $α$. This study reveals the essential role of magneto anisotropic energy in the interpretation of the magnetic behaviour of a collection of noninteracting single domain nanoparticles.

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Malay Bandyopadhyay. 2011-12-17. Thermodynamic properties of magneto-anisotropic nanoparticles. https://arxiv.org/abs/0706.3661

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