Wideband microwave signal to trigger fast switching processes in magnetic tunnel junctions

A different method to supply magnetic random access memories (MRAM) cells based on spin-transfer torque resonant switching is presented based on a micromagnetic study. Microwave excitation can significantly reduce the current density needed to obtain the switching for making the writing current compatible with CMOS technology. Nevertheless the practical application of this strategy to the write/read process of MRAM cells matrix is hampered by the variation of the physical and geometric parameters that leads to a spreading of the resonance frequency. Here, we propose a robust method that contextually allows resonant switching and decreases the power dissipation.

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