Comparison of noninvasive and remote temperature estimation employing magnetic nanoparticles in DC and AC applied fields

This paper examines the advantages and disadvantages of noninvasive and remote temperature estimation employing magnetic nanoparticles (MNPs) in DC and AC applied fields. A Langevin function that describes the magnetization of the MNPs in different applied magnetic fields is investigated to obtain a noninvasive and remote measurement of on-site temperature using MNPs. Several nonlinear functions, in which temperature and concentration are independent variances, are found by discretizing the Langevin function model of the magnetization of MNPs. Then, the temperature estimation range from 310 K to 350 K is transformed to the solution of the nonlinear function using the temperature independence of the saturation magnetization of the MNPs.