Micromagnetic Simulations of Copt: Investigation of Domain Wall Pinning

Open Access
Johnson, Zach Donald
Area of Honors:
Materials Science and Engineering
Bachelor of Science
Document Type:
Thesis Supervisors:
  • Roman Engel Herbert, Thesis Supervisor
  • Robert Allen Kimel, Honors Advisor
  • materials
  • material
  • micromagnetic
  • simulation
  • simulations
  • CoPt
  • Cobalt
  • Platinum
  • Co-Pt
  • domain
  • domains
  • pinning
  • defect
This thesis presents results for the micromagnetic simulation investigation of domain wall pinning in the material system CoPt. Defect sites were modeled as areas with a higher anisotropy than the rest of the CoPt in order to create an area resistant to a change in magnetization. Domain wall displacement was studied as a function of defect pinning strength and defect pinning distance. It was found that as the defect distance increases, the domain wall becomes “looser” and propagates through the material system further at the same value of external magnetic field. Furthermore, the energy contributions to the magnetic system were investigated in order to explain the nature of the propagation of the domain wall movement. Finally, a study of anisotropy energy as a function of domain wall displacement is presented, in order to correlate the energy of the magnetic system directly to the distance that a domain wall is displaced. In this way, it would be possible to predict the domain wall displacement of a material system, if the energies of the system are known.