Parametric mechanism of the magnetization reversal as a low-power recording mechanism for MRAM. Measurement of spin-accumulation-induced in-plane magnetic field in a FeB nanomagnet

Abstract: The parametric torque presents a promising recording mechanism for MRAM, complementing Spin Transfer Torque and Spin Orbit Torque, enabling magnetization reversal in a nanomagnet using a DC electrical current. Its resonance nature allows for optimization of magnetization reversal at a lower current, presenting an opportunity for a lower recording current and, therefore, for efficient and high-performance operation in modern MRAM technology. The in-plane magnetic field generated by spin accumulation serves as the driving force behind this torque. Experimental measurements of the current-induced in-plane magnetic field in the FeB nanomagnet reveal its magnitude to be around 40 Gauss at a current density of 25 mA/$\mu m^2$, a value adequate for facilitating parametric magnetization reversal. The parametric torque is analytically calculated by solving the Landau-Lifshitz equation. Analytical calculations demonstrate its potential in advancing modern MRAM technology.