Electric-field-induced three-terminal pMTJ switching in the absence of an external magnetic field

Since it is undesirable to require an external magnetic field for on-chip memory applications, we investigate the use of a Rashba effective field alternatively for assisting the electric-field-induced switching operation of a three terminal perpendicular magnetic tunnel junction (pMTJ). By conducting macro-spin simulation, we show that a pMTJ with thermal stability of 61 can be switched in 0.5 ns consuming a switching energy of 6 fJ, and the voltage operation margin can be improved to 0.8 ns. Furthermore, the results also demonstrate that a heavy metal system that can provide large field-like torque rather than damping-like torque is favored for the switching.

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