Tailoring the magnetic properties of Co20Fe60B20/SmCo5 bilayers: Effects of argon ion implantation.

• 10 keV Ar+ ion implantation induced modifications has been explored in Co 20 Fe 60 B 20 /SmCo 5 bilayers. • Magnetic Coercivity has been increased by more than ten times after implantation. • X-ray reflectivity study revealed ion implantation causes significant microstructural modifications. • Enhancement of coercivity attributed to mixing of elements at the interface and Ar implantation induced defects creation. 10 keV Ar+ ion implantation induced modifications of nanoscale Co 20 Fe 60 B 20 /SmCo 5 /Si-substrate heterostructures have been investigated. Magneto-optic Kerr effect study reveals that the coercivity enhances by more than ten times after implantation. Implantation gives rise to an increase in surface roughness and densely packed grains as evident from the Atomic Force Microscopy study. X-ray reflectivity analysis manifests ion beam induced intermixing between elements of two layers at the interface and significant changes in the internal structure. Monte Carlo simulation study corroborates the x-ray reflectivity results. Enhancement of coercivity attributed to interface mixing and implantation induced defect creation in the films. [ABSTRACT FROM AUTHOR]