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Magnetization of polydisperse colloidal ferrofluids: Effect of magnetostriction

J. P. Huang·C. Holm
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Abstract

We exploit magnetostriction in polydisperse ferrofluids in order to generate nonlinear responses, and apply a thermodynamical method to derive the desired nonlinear magnetic susceptibility. For an ideal gas, this method has been demonstrated to be in excellent agreement with a statistical method. In the presence of a sinusoidal ac magnetic field, the magnetization of the polydisperse ferrofluid contains higher-order harmonics, which can be extracted analytically by using a perturbation approach. We find that the harmonics are sensitive to the particle distribution and the degree of field-induced anisotropy of the system. In addition, we find that the magnetization is higher in the polydisperse system than in the monodisperse one, as also found by a recent Monte Carlo simulation. Thus, it seems possible to detect the size distribution in a polydisperse ferrofluid by measuring the harmonics of the magnetization under the influence of magnetostriction.

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J. P. Huang, C. Holm. 2004-07-30. Magnetization of polydisperse colloidal ferrofluids: Effect of magnetostriction. https://doi.org/10.1103/physreve.70.061404

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