Magnons in Co dot

Eigen spin wave frequencies and profiles of a cobalt hexagonal dot with exchange and anisotropy energies are derived. The lowest mode frequency is shown to be a linear function of edge anisotropy, so edge anisotropy controls the whole dot magnetization reversal and can be measured from spin wave resonance. The low-temperature dependence of cobalt dot magnetization is shown to be driven by edge anisotropy as well. (c) 2006 Elsevier B.V. All rights reserved.