Switching field and thermal stability of CoPt/Ru dot arrays with various thicknesses


Mitsuzuka, K. and Kikuchi, N. and Shimatsu, T. and Kitakami, O. and Aoi, H. and Muraoka, H. and Lodder, J.C. (2007) Switching field and thermal stability of CoPt/Ru dot arrays with various thicknesses. IEEE Transactions on Magnetics, 43 (6). pp. 2160-2162. ISSN 0018-9464

Abstract:The switching fields and thermal stability of CoPt/Ru dot arrays with various dot thickness delta (5-20 nm) were experimentally investigated as a function of the dot diameter, D, (130-300 nm). All dot arrays showed a single domain state, even after removal of an applied field equal to the remanence coercivity Hr. The angular dependence of Hr for the dot arrays indicated coherent rotation of the magnetization during nucleation. We estimated the values of the "intrinsic" remanence coercivity H0 obtained by subtracting the effect of thermal agitation on the magnetization and the stabilizing energy barrier to nucleation E0/(kBT). The variation in H0 as a function of delta and D was qualitatively in good agreement with that of the effective anisotropy field at the dot center Hk eff(r=0), calculated taking account of the demagnetizing field in the dots. The ratio of H 0 to Hk eff(r=0) for the dot arrays with delta=10 nm increased from 0.53 to 0.70 as D decreased from 300 to 140 nm, and no significant difference in the H0/Hk eff(r=0) ratio due to the difference in delta was observed. On the other hand, E0/(k BT) decreased as delta decreased. E0/(kBT) increased slightly as D decreased, but, was not so sensitive to D over the present D range
Item Type:Article
Copyright:© 2007 IEEE
Electrical Engineering, Mathematics and Computer Science (EEMCS)
Research Group:
Link to this item:http://purl.utwente.nl/publications/67103
Official URL:http://dx.doi.org/10.1109/TMAG.2007.893129
Export this item as:BibTeX
HTML Citation
Reference Manager


Repository Staff Only: item control page

Metis ID: 241624