Simulating magnetization dynamics of large ensembles of single domain nanoparticles: Numerical study of Brown/Néel dynamics and parameter identification problems in magnetic particle imaging

Publikationstyp
Journal Article
Date Issued
2022-01-01
Sprache
English
Author(s)
Albers, Hannes  
Kluth, Tobias  
Knopp, Tobias  
Institut
Biomedizinische Bildgebung E-5  
TORE-URI
http://hdl.handle.net/11420/10418
Journal
Journal of magnetism and magnetic materials  
Volume
541
Article Number
168508
Citation
Journal of Magnetism and Magnetic Materials 541: 168508 (2022-01-01)
Publisher DOI
10.1016/j.jmmm.2021.168508
Scopus ID
2-s2.0-85115373510
Magnetic nanoparticles and their magnetization dynamics play an important role in many applications. We focus on magnetization dynamics in large ensembles of single domain nanoparticles being characterized by either Brownian or Néel rotation mechanisms. Simulations of the respective behavior are obtained by solving advection–diffusion equations on the sphere, for which a unified computational framework is developed and investigated. This builds the basis for solving two parameter identification problems, which are formulated in the context of the chosen application, magnetic particle imaging. The functionality of the computational framework is illustrated by numerical results in the parameter identification problems either compared quantitatively or qualitatively to measured data.
Subjects
Advection–diffusion equation
Brown/Néel rotation
Fokker–Planck equation
Magnetic nanoparticles
Magnetic particle imaging
Parameter identification