Magnetic switching probability of perpendicularly magnetized nano-dot

Abstract

Understanding of magnetization reversal mode plays an important role in spintronic devices performance. Especially in Heat Assisted Magnetic Recording, the contribution of thermal field in the magnetization dynamics becomes a crucial aspect which should be further explored. In this paper, Landau Lifshift-Gilbert equation was employed to investigate the magnetic switching dynamics for nano-dots with different magnetic anisotropies. This micromagnetic study shows that these nano-dots exhibit the different mode of switching. Multi-domain configuration dictates the switching process for nano-dot with strong magnetic anisotropy before magnetized in the driven magnetic field direction. Meanwhile, multi-domain configuration, domain-wall nucleation, and propagation take place in the process to achieve magnetized single-domain for the nano-dot with the lower level of magnetic anisotropy. Furthermore, in the absence of the external magnetic field, magnetic moments of this low magnetic anisotropies nano-dot is more probably to reverse.