Nonlinear vortex gyrotropic motion in a three-nanocontacts system is investigated by micromagnetic slmulations and analytical calculations. Three out-of-plane spin-polarized currents are injected into a nanodisk throu...Nonlinear vortex gyrotropic motion in a three-nanocontacts system is investigated by micromagnetic slmulations and analytical calculations. Three out-of-plane spin-polarized currents are injected into a nanodisk through a centered nanocontact and two off-centered nanocontacts, respectively. For current combination （ipl, ip0, ip2） = （-1,1, -1）, the trajectory of the vortex core is a peanut-like orbit, but it is an elliptical orbit for （ip1, ip0, ip2） = （1, 1, -1）. Moreover, the gyrotropic frequency displays peaks for both current combinations. Analytical calculations based on the Thiele equation show that the changes of frequency can be ascribed mainly to the forces generated by the Oersted field accompanying the currents. We also demonstrate a dependence of eigenfrequency shifts on the direction and distance of the applied currents.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.11404053)the Fundamental Research Funds for the Central Universities of Ministry of Education of China(Grant No.n130405011)
文摘Nonlinear vortex gyrotropic motion in a three-nanocontacts system is investigated by micromagnetic slmulations and analytical calculations. Three out-of-plane spin-polarized currents are injected into a nanodisk through a centered nanocontact and two off-centered nanocontacts, respectively. For current combination （ipl, ip0, ip2） = （-1,1, -1）, the trajectory of the vortex core is a peanut-like orbit, but it is an elliptical orbit for （ip1, ip0, ip2） = （1, 1, -1）. Moreover, the gyrotropic frequency displays peaks for both current combinations. Analytical calculations based on the Thiele equation show that the changes of frequency can be ascribed mainly to the forces generated by the Oersted field accompanying the currents. We also demonstrate a dependence of eigenfrequency shifts on the direction and distance of the applied currents.
