摘要:
利用Monte Carlo (蒙特卡洛)方法结合快速傅立叶变换，研究了不同缺陷环半径、不同缺陷位置的纳米环磁特性，模拟结果表明：纳米环系统缺陷程度较小时，其磁特性与对称纳米环系统接近；而当缺陷程度较大时，由于其几何形状与对称单纳米环相差甚远，系统的磁特性与对称纳米环系统差别较大。此外，研究还发现，缺陷程度较大时，系统虽保留了对称纳米环系统的主要特征(涡旋态和洋葱态)，但相比起来，涡旋态的稳定性更低，过渡状态增加，整体的磁化过程也更为复杂。
Abstract:
Based on the Monte-Carlo simulation and fast Fourier transformation micro-magnetism method, the magnetic properties of Co nanorings with different defect locations are studied. The simula-tion results show that the magnetic properties of the nanorings with small defect degree are similar to those of symmetric nanorings. With the defect degree increasing, the magnetic dynamic behavior of defect nanorings is obviously different from that of symmetric nanorings. The results also indicate that the defect system keeps the main magnetic characteristic of the symmetric nanorings (such as vortex state and onion state). Compared to the symmetric nanorings, the stability of defect nanorings is weak. Furthermore, with the defect degree increasing, the number of transition states in nanoring system increases, and magnetization process becomes complex.