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arXiv · 1208.5347

Hysteresis in a magnetic bead and its applications

Vanchna Singh·Varsha Banerjee
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Abstract

We study hysteresis in a micron-sized bead: a non-magnetic matrix embedded with super- paramagnetic nanoparticles. These hold tremendous promise in therapeutic applications as heat generating machines. The theoretical formulation uses a mean-field theory to account for dipolar interactions between the supermoments. The study enables manipulation of heat dissipation by a compatible selection of commercially available beads and the frequency f and amplitude ho of the applied oscillating field in the labortory. We also introduce the possibility of utilizing return point memory for gradual heating of a local region.

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Vanchna Singh, Varsha Banerjee. 2012-08-27. Hysteresis in a magnetic bead and its applications. https://doi.org/10.1063/1.3567732

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