Temporal evolution of magnetization in a field cooling process from magnetic ordering temperature has been numerically investigated
for magnetic nanodots with perpendicular anisotropy by solving the stochastic Landau–Lifshitz–Gilbert equation. The magnetic field
required to align the magnetization, i.e. the switching field for thermally assisted writing of magnetic dot, depends on not only the
intrinsic anisotropy field but also the magnetization reversal mechanism. To minimize the switching field with ensuring a practical
thermal stability of the dot for nonvolatile memory applications, the lateral dimension of the dot should be smaller than its critical size
for single domain configuration to avoid a formation of flux closure configuration inside the dot.
Keywords: Numerical simulation; Nanodot magnetic; Perpendicular anisotropy; Thermally assisted; Magnetization reversa
