Manipulation of magnetic state in nanostructures by perpendicular anisotropy and magnetic field

作者:Chen, J P*; Xie, Y L; Chu, P; Wang, Z Q; Wang, Y L; Gao, X S; Liu, J M
来源:Journal of Applied Physics, 2014, 115(24): 243910.
DOI:10.1063/1.4885158

摘要

We investigate the transitions of spin configurations in ultrathin nanostructures by tuning the perpendicular anisotropy (K-z) and out-of-plane magnetic field (H), using the Monte Carlo simulation. It is revealed that enhancing the anisotropy K-z can drive the evolution of in-plane vortex state into intriguing saturated magnetization states under various H, such as the bubble domain state and quadruple-block-domain state etc. The spin configurations of these states exhibit remarkable H-dependence. In addition, the strong effects of geometry and size on the spin configurations of nanostructures are observed. In particular, a series of edged states occur in the circular disk-shaped lattices, and rich intricate saturated magnetization patterns appear in big lattices. It is suggested that the magnetic states can be manipulated by varying the perpendicular anisotropy, magnetic field, and geometry/size of the nanostructures. Furthermore, the stability (retention capacity) of the saturated magnetization states upon varying magnetic field is predicted, suggesting the potential applications of these saturated magnetization states in magnetic field-controlled data storages.