Magnetic anisotropy and magnetization reversal processes in Pt/Co/Pt films

Modification of Magnetic Properties of Pt/Co/Pt Films by Ga+ Ion Irradiation: Focused versus Uniform Irradiation

“…The first goal of the present article is to compare the uniform 30 keV Ga + ion-irradiation-induced magnetic changes in Pt/Co(d Co )/Pt sputter-grown films with those ones previously reported for their MBE-grown counterparts [22], for both out-of-plane (d Co < d SRT ) and in-plane (d Co > d SRT ) magnetized pristine films [6]. Sputtering is an important technique of deposition of magnetic nanostructures.…”

“…For irradiation by light He + ions, structural and magnetic changes arise only from ballistic ion collisions that favor disordering and intermixing at Co-Pt interfaces. Generally, ionbombardment-driven modifications of Co films can be considered for two ranges of cobalt thickness d Co , namely smaller or larger than d SRT -the critical Co thickness at the out-of-plane to in-plane spin reorientation transition (SRT) [6]. Considering Pt/Co(d Co )/Pt pristine films with PMA (d Co < d SRT ), irradiation by He + * corresponding author; e-mail: jo@uwb.edu.pl ions reduces the magnetic interface anisotropy contribution [1,3], the coercivity [1,7] and the Curie temperature [7,8] to finally trigger a SRT [9,10].…”

Dynamic selective switching in antiferromagnetically-coupled bilayers close to the spin reorientation transition

“…20 Finally, we should remark that the effect studied here will only occur in SAFs formed by two layers with (different) thicknesses close to the SRT, since a net coupling field between layers is required. Ultra-thin films with strong PMA and thick films where the magnetization is purely in plane also have significantly different dynamic switching field dependences; 11,13 however, in a SAF formed by these two types of layers and under uniaxial coupling, selective dynamic switching as the one studied in this work will not be possible, since the system will present zero inter-layer coupling as the magnetization of the layers will lie at 90 degrees from each other.…”

“…For t ¼ 2 nm, a hard axis loop is observed, with a low saturation field ($500 Oe), as expected for a film just thicker than t c . 13 The switching of this layer occurs mostly via coherent rotation of the magnetization. The small hysteresis loop observed is due either to field misalignment or to a small number of out-of-plane domains likely caused by small thickness variations along the sample.…”

“…In summary, coercive fields, domain structure, and magnetization reversal mechanism depend critically on film thickness close to the SRT, due to the large changes in K eff for this thickness range. 10,13 We show the magnetization reversal dynamics of the samples through the sweep rate dependent coercivity in Fig. 1(i).…”