Spin Torque Transfer Magnetoresistance

Spin Torque Transfer MRAM is a well-known device that75176

 exhibits memristive behavior. The resistance is dependent on the relative spin orientation between two sides of a magnetic tunnel junction. This in turn can be controlled by the spinKA2209

 torque induced by the current flowing through the junction. However, the length of time the current flows through the junction determines the amount of current needed, the charge flowing through is theIRF1010E

 key variable.Additionally, as reported by Krzysteczko et al.,MgO based magnetic tunnel junctions show memristive behavior based on the drift of oxygen vacancies within the insulating MgO layer (resistive switching).NE602AN

 Therefore, the combination of spin transfer torque and resistive switching leads naturally to a second-order memristive system with where w1 describes the magnetic state of the magnetic tunnel junction and denotes the resistive state of the2SK241

 MgO barrier. Note that in this case the change of w1 is current-controlled (spin torque is due to a high current density) whereas the change of is voltage-controlled (the drift of oxygen vacancies is due to high electric fields).