Domain Wall Dynamics Due to Voltage Controlled Magnetic Anisotropy

摘要

We study domain wall motion due to spin-polarized currents. This motion is caused by the spin transfer torque acting on the domain wall (or on any change encountered in the magnetization per se), provided by the electrons of the spin-polarized current. The main drawback of the current induced domain wall motion lies in the fact that the current density (of the spin polarized currents) required for an adequately fast domain wall motion is quite high. Our study also includes the effects of Voltage Controlled Magnetic Anisotropy on the current induced domain wall motion. Voltage Controlled Magnetic Anisotropy, being completely a voltage based approach, reduces the power requirements enormously, as the current density requirement for the same domain wall speed reduces. We present the results for both out-of-plane and in-plane magnetized wires. The Voltage Controlled Magnetic Anisotropy coupled with the well-established notion of current induced domain wall motion increases the future potential of such memory devices (like MRAMs) even further by bringing down the power consumption.