尺寸对椭圆钴纳米环磁特性的影响

The Size Effects of the Magnetic Properties for Ellipse Co Nanorings

利用Monte-Carlo方法模拟了不同长、短轴以及不同内径的椭圆钴纳米环的磁特性.模拟结果表明:对于偏心率较小的椭圆钴纳米环,当内径不大时,系统的磁滞回线与圆形钴纳米环的磁滞回线相当类似;当内径较大时,系统的磁滞回线与圆形钴纳米环的结果有很大的不同.当椭圆的偏心率增大时,由于存在较多的过渡状态,系统磁滞回线的台阶变得更为平滑,这可以通过系统的磁化过程进行解释.当椭圆的偏心率较大时,由于出现了大量的过渡状态,系统的磁滞回线呈现的台阶变得更加平滑.

Base on the Monte-Carlo simulation, the effect of different major axis, minor axis and interior diameter for ellipse Co nanorings are studied. It is found that magnetic hys-teresis loop of ellipse Co nanorings and circular Co nanorings are similar when eccentricity and interior diameter is less. However, there is a big difference between magnetic hysteresis loop of ellipse Co nanorings and circular Co nanorings when eccentricity is less and interior diameter is bigger. When eccentricity is augmented, step of magnetic hysteresis loop become smooth because of more transitional states. These phenomena can be explained by magneti- zation process. If eccentricity is increasing, a lot of transitional states are observed and step of magnetic hysteresis loop become smoother.