Langevin dynamic simulations of magnetic hyperthermia in rotating fields

• Published in: Journal of magnetism and magnetic materials 2023-01, Vol.565, p.170171, Article 170171
• Main Authors: Gontijo, R.G., Guimarães, A.B.
• Format: Article
• Language: English
• Subjects: Complex susceptibility; Magnetic fluids; Magnetic hyperthermia; Rotating magnetic field
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2022.170171

The effect of a rotating magnetic field on heat dissipation due to magnetic hyperthermia is investigated numerically. A robust and validated in-house code based on Langevin Dynamics is used. High order asymptotic solutions of the temperature rate are used to validate the numerical approach. Comparisons between a rotating and an oscillatory excitation indicate a nonlinear response of the magnetic suspension with respect to the amplitude and frequency of the field. The relaxation time and volume fraction of particles also play a relevant role in this dynamics. A complete analysis on the effect of these parameters on the thermal response of the system is presented. The timescales of the problem and geometric features of the suspension micro-structure are used to interpret the results. Hysteresis curves and the real and imaginary components of the complex susceptibility are also presented in order to provide a clear physical description of the problem. •Numerical evaluation of the LD approach as a tool to avail heat induction in MHT;•Comparison between the thermal response tumour under rotating and oscillatory field;•Use of Ewald summation to compute the role of long-range dipolar interactions;