Switching the in-plane easy axis by ion implantation in rare earth based magnetic films

Abstract

Ar(+) ions have been implanted into Laves phase epitaxial thin films of YFe(2) and DyFe(2). Magneto-optical Kerr effect and vibrating sample magnetometry experiments show that the easy and hard axes of magnetization in both materials rotate through an in-plane angle of 90°, whilst the strength of the magnetic anisotropy remains unaltered. This is supported by OOMMF computational modelling. Atomic force microscopy confirms that the film roughness is not affected by implanted ions. X-ray diffraction data show that the lattice parameter expands upon ion implantation, corresponding to a release of strain throughout the entire film following implantation with a critical fluence of 10(17) Ar(+) ions cm(-2). The anisotropy of the films is linked to the strain and from these data it is concluded that the source of anisotropy alters from one where magnetoelastic and magnetocrystalline effects compete to one which is governed solely by magnetocrystalline effects. The ability to locally tune the source of magnetic anisotropy without affecting the film surface and without inducing or eliminating anisotropy could be important in the fabrication of high density magnetic data storage media, spintronic devices and magneto-optical materials.

Magnonic band structure of domain wall magnonic crystals

“…To get numerical values, we need to specify the magnetic parameters. The magnetic parameters in the two regions should be different to get sizable energy gaps, which can be realized by ion implantation 12,13 or using artificial superlattices 36,37 . However, it should be noted that, in contrast to conventional 1D MCs, DWMCs have energy gaps even if regions 1 and 2 have the same set of magnetic parameters (cf.…”

“…The magnetic materials in the two regions could be identical or different. For a usual MC, in order to induce an energy gap for SWs, the magnetic parameters of the two regions have to be different, which can be realized by using different materials or local modification of the magnetic properties of the same material through ion implantation 12,13 . In our simplified 1D treatment of DWMCs, what matters is the magnetic parameters in the two regions, which are differentiated by the subscripts 1 and 2 for regions 1 and 2, respectively.…”

Patterning effects on magnetic reversal properties in epitaxial-grown Laves phase DyFe2/YFe2 superlattice

“…The direction of easy magnetization of the RE-Fe 2 compounds is determined by the magnetocrystalline anisotropy associated with RE 3 þ ions [9]. It has been demonstrated that the magnetic anisotropy of the RE-Fe 2 films, as a basic role playing in the magnetic reversal process, can be modified by ion irradiation or patterning [10]. By patterning epitaxial 400-nmthick RE-Fe 2 films into micro-sized stripes shape anisotropy in the order of 10 5 erg/cm 3 in magnitude can be created [11][12][13].…”