Magnetization reversal and switching field of CoPt/Ru patterned films


Mitsuzuka, K. and Shimatsu, T. and Muraoka, H. and Kikuchi, N. and Lodder, J.C. (2006) Magnetization reversal and switching field of CoPt/Ru patterned films. Journal of the Magnetics Society of Japan, 30 (2). pp. 100-107. ISSN 0285-0192

[img] PDF
Restricted to UT campus only
: Request a copy
Abstract:Dot arrays with diameter D = 80-245 nm were made from Co80Pt20 (20 nm) films with a large perpendicular anisotropy energy. Coercivity increases as D decreases, and reaches 7.6 kOe at D = 80 nm. The switching volume for the dot arrays, estimated from the field sweep-rate dependence of the coercivity, was very small in comparison with the dot volume: about 7% of the dot volume when D = 140 nm, for instance. However, the angular dependence coercivity of these dots exibits a typical rotational type of magnetization reversal. Moreover, MFM images revealed that all the dots show a single domain state during the magnetization reversal. Comparison of the coercivity and the anisotropy field suggests that the reversal process starts from a nucleation at the center of the dot followed by a propagation process. This possibility was confirmed by numerical calculation. It was estimated that the switching field distribution, SFD, of dot arrays was mainly due to the distributions of the c-axis of the hcp-CoPt lattice and the dot diameter. Calculated results indicate that the magneto-static coupling between the dot arrays must be a dominant factor in determining the SFD value when the dots are used for patterned media with a recording density of ∼1 Tbits/inch2.
Item Type:Article
Electrical Engineering, Mathematics and Computer Science (EEMCS)
Research Group:
Link to this item:
Official URL:
Export this item as:BibTeX
HTML Citation
Reference Manager


Repository Staff Only: item control page

Metis ID: 248226