Abstract:
The dynamics of the magnetization vector in the free layer of a layered spin-valve structure was simulated. As materials for the free and fixed layers, six magnetically soft ferromagnets with longitudinal anisotropy were considered. The types of magnetization dynamics that are of practical interest for MRAM and HMDD (switching of the magnetization vector), STNO (stable precession of the magnetization vector), and the base element PSL (switching of the magnetization vector with two probable outcomes) were highlighted. The ranges of currents and fields corresponding to these operating modes of the spin valve were calculated. The numerical calculations of the switching time showed that, among the considered materials for the MRAM cell, the most suitable is Co$_{80}$Gd$_{20}$ alloy, while for the HMDD read head, it is Fe$_{60}$Co$_{20}$B$_{20}$. As a result of the precession frequency calculations, it was concluded that the Fe$_{60}$Co$_{20}$B$_{20}$ alloy is optimal for the STNO ferromagnetic layers. For the implementation of PSL, the best switching characteristics were demonstrated by the Co$_{93}$Gd$_{7}$ alloy.
Keywords:spin valve, magnetoresistive random-access memory, probabilistic spin logic, spin-transfer nano-oscillator, read head of the hard disk.