Faster vortex core switching with lower current density using three-nanocontact spin-polarized currents in a confined structure**Project supported by the China Postdoctoral Science Foundation (Grant No. 2013M541286), the Science and Technology Planning Project of Jilin Province, China (Grant Nos. 20140520109JH and 20150414003GH), and the “Twelfth Five year” Scientific and Technological Research Project of Department of Education of Jilin Province, China.

Abstract

We perform micromagnetic simulations on the switching of magnetic vortex core by using spin-polarized currents through a three-nanocontact geometry. Our simulation results show that the current combination with an appropriate current flow direction destroys the symmetry of the total effective energy of the system so that the vortex core can be easier to excite, resulting in less critical current density and a faster switching process. Besides its fundamental significance, our findings provide an additional route to incorporating magnetic vortex phenomena into data storage devices.