Domain wall formation in dipolar NP assemblies

Longitudinal domain wall formation in elongated assemblies of ferromagnetic nanoparticles.
Miriam Varón, Marco Beleggia, Jelena Jordanovic, Jakob Schiøtz, Takeshi Kasama, Victor F. Puntes & Cathrine Frandsen
Scientific Reports 5, 14536 (2015)

Simulation of the relaxed F-state (a–c) and the relaxed L-state (d–f) with increasing reverse fields of (a,d) 0 mT, (b,e) 35 mT, and (c,f) 50 mT. The colors denote the orientation of the magnetic moment (cf. the color wheel in Fig. 3). Panels on the right hand side indicate the net moment in the length direction over the widths of the assemblies.