Formation of magnetic nanocolumns during vapor phase deposition of a metal-polymer nanocomposite: Experiments and kinetic Monte Carlo simulations

• Published in: Journal of applied physics 2013-07, Vol.114 (4)
• Main Authors: Rosenthal, L., Greve, H., Zaporojtchenko, V., Strunskus, T., Faupel, F., Bonitz, M.
• Format: Article
• Language: English
• Subjects: Computer simulation; Deposition; Iron; Monte Carlo methods; Nanocomposites; Nanomaterials; Nanostructure; Vapor phases
• ISSN: 0021-8979; 1089-7550
• DOI: 10.1063/1.4816252

Metal-polymer nanocomposites have been investigated extensively during the last years due to their interesting functional applications. They are often produced by vapor phase deposition which generally leads to the self-organized formation of spherical metallic nanoparticles in an organic matrix, while nanocolumns are only obtained under very specific conditions. Experiments [Greve et al. Appl. Phys. Lett. 88, 123103 (2006)] have shown that co-evaporation of the metallic and organic components in a simple single-step process can give rise to the formation of ultrahigh-density Fe-Ni-Co nanocolumnar structures embedded in a fluoropolymer matrix. Here we present a kinetic Monte Carlo approach which is based on a new model involving the depression of the melting point on the nanoscale and a critical nanoparticle size required for solidification. In addition we present new experimental results on the formation of Fe-Ni-Co nanocolumns in a Teflon AF matrix via co-evaporation down to a deposition temperature of −70 °C and also report the magnetic properties of the nanocolumns. The simulations provide a detailed understanding of the transition from spherical cluster growth to formation of elongated structures and are in good agreement with the experiments.