We demonstrate how the magnetic properties of metal=dielectric Co=yttrium iron garnet heterostructures can be engineered by both changing the garnet thickness and adding an ultrathin Co cover layer. The observed magnetization reversal process in the heterostructures is explained by both cubic and perpendicular growth-induced magnetic anisotropy of the garnet films. In particular, the perpendicular magnetic anisotropy can be strongly increased for reduced thickness. A strong influence of a 2 nm Co layer on the domain structure geometry and magnetization processes has been found for 1.8 lm garnet films.

Effect of a change in thickness on the structural and perpendicular magnetic properties of L10 ordered FePd ultra-thin films with (001) texture J. Appl. Phys. 112, 113919 (2012) Spacer-less, decoupled granular L10 FePt magnetic media using Ar-He sputtering gas J. Appl. Phys. 112, 113916 (2012) Development of FeNiMoB thin film materials for microfabricated magnetoelastic sensors J. Appl. Phys. 112, 113912 (2012) Room-temperature ferromagnetism induced and controlled by electric field in BaNbO3 films

No abstract

-We report on magnetization dynamics triggered in a Co/garnet heterostructure by femtosecond laser pulses. Although laser excitation of a bare Co-doped yttrium iron garnet leads to magnetization precession, the phase of which strongly depends on the linear polarization of the light pulses, the deposition of an ultrathin Co layer on a top of a garnet film results in substantial changes of the laser-induced dynamics. The precession in the garnet is shown to lose its sensitivity to the polarization. Instead, light triggers polarization insensitive precession in both the magnetostatically coupled Co layer and the garnet film at two distinct frequencies typical for Co and garnet layers.

No abstract