抄録
A computer simulation has been made for a calculation of technical magnetization curves of magnetic small particles in nanometer scale by assuming surface anisotropy acting in addition to existing magneto-crystalline anisotropy in bulk (a particle body). A particle shape modeled is a cylinder, in which a variable particle size of 30, 40, 50 and 60 rim in diameter with a fixed height of 30 nm for each is considered. Micro-magnetic calculations, based on Landau-Lifshitz-Gilbert equation, indicate an enhanced coercivity for a magnetic single-domain particle with the smaller particle size and also with the stronger surface anisotropy acting there, in accord with the existing coercivity data for various materials in small particle forms.
