Domain wall generated by graded interlayer coupling in Co/Pt/Co film with perpendicular anisotropy

• DOI: 10.1063/1.4926357
• Publication Date: 2015-07-06T17:22:06Z
• Authors: M. Matczak; R. Schäfer; M. Urbaniak; B. Szymański; P. Kuświk; A. Jarosz; M. Schmidt; J. Aleksiejew; S. Jurga; F. Stobiecki
• Keywords: 0103 physical sciences; 01 natural sciences

A magnetic multilayer of the structure substrate/Pt-15 nm/Co-0.8 nm/Pt-wedge(0-7 nm)/Co-0.6 nm/Pt-2 nm is characterized by perpendicular anisotropy of both Co layers. For a Pt spacer thickness tPt≤2.6nm, the magnetization reversal of the Co-layers occurs cooperatively, while for larger tPt, it occurs sequentially. The Co-layer with 0.6 nm thickness (CoS) is magnetically softer than the second one (CoH). In the 2.6≤tPt≤3.0 nm range, there are significant changes of the switching field due to a strong gradient of the interlayer coupling. In this region, the magnetization reversal in the CoS layer takes place reversibly by the propagation of a single, straight domain wall. This specific nature of magnetization reversal is explained by a decelerated motion of the domain wall observed both for the direction corresponding to the increasing, as well as decreasing coupling energy.