Spin wave-assisted enhanced current-driven domain wall movement

Abstract

The track memory based on current driven magnetic domain wall motion is a potential device for the next generation of magnetic information storage. To improve the speed of current driven domain wall motion and reduce the Joule heat, the relevant laws and physical mechanisms of the spin wave assisting current driven domain wall motion in long linear magnetic nanoribbons has been investigated to achieve spin wave assisted enhancement of current driven domain wall motion. The results show that the spin wave assisting can both enhances and weakens current driven domain wall motion depends on the driving current. Further research has shown that, for giving frequency spin waves, in the low current, spin wave assistance can enhance the current driven magnetic domain wall movement, and the enhancement of its movement speed increases non-monotonically with the increase of spin wave amplitude, but in the high current, spin wave assistance weakens the current driven magnetic domain wall movement, and the weakening of its movement speed nearly linear increases with the increase of spin wave amplitude. The critical current for distinguishing between the high and the low current depends on the amplitude and frequency of the assisting spin wave. On the other hand, for giving the amplitude spin wave, the increase or decrease of the spin wave assisting current driven domain wall motion exhibits a multimodal non-monotonic behavior as the frequency of the spin wave increases. Therefore, the appropriate spin wave assisting track storage technology can reduce the threshold current of track memory operation, making it more widely used. Also it can reduce Joule heat and improve the working efficiency of track memory.