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arXiv · 1702.02022

Giant-spin nonlinear response theory of magnetic nanoparticle hyperthermia: a field dependence study

Marcus S. Carrião·Victor R. R. Aquino·Gabriel T. Landi·Ediron L. Verde·Marcelo H. Sousa·Andris F. Bakuzis
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Abstract

Understanding high-field amplitude electromagnetic heat loss phenomena is of great importance, in particular in the biomedical field, since the heat-delivery treatment plans might rely on analytical models that are only valid at low field amplitudes. Here, we develop a nonlinear response model valid for single- domain nanoparticles of larger particle sizes and higher field amplitudes in comparison to linear response theory. A nonlinear magnetization expression and a generalized heat loss power equation are obtained and compared with the exact solution of the stochastic Landau-Lifshitz-Gilbert equation assuming the giant-spin hypothesis. The model is valid within the hyperthermia therapeutic window and predicts a shift of optimum particle size and distinct heat loss field amplitude exponents. Experimental hyperthermia data with distinct ferrite-based nanoparticles, as well as third harmonic magnetization data supports the nonlinear model, which also has implications for magnetic particle imaging and magnetic thermometry.

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Marcus S. Carrião, Victor R. R. Aquino, Gabriel T. Landi, Ediron L. Verde, Marcelo H. Sousa, Andris F. Bakuzis. 2017-02-07. Giant-spin nonlinear response theory of magnetic nanoparticle hyperthermia: a field dependence study. https://doi.org/10.1063/1.4982357

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