Magnetization of polydisperse colloidal ferrofluids: Effect of magnetostriction
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.
Keywords
Cite
@article{arxiv.cond-mat/0407650,
title = {Magnetization of polydisperse colloidal ferrofluids: Effect of magnetostriction},
author = {J. P. Huang and C. Holm},
journal= {arXiv preprint arXiv:cond-mat/0407650},
year = {2009}
}
Comments
23 pages, 4 figures. To be accepted for publication in Phys. Rev. E