SPICE models for single domain magnetic nano-pillar tunnel junction arrays

A magnetic tunnel junction, used as a memory element in a magnetic random access memory, can be switched by a spin polarized current flowing through the MTJ. We developed a single domain model for the MTJ and magnetostatically coupled interaction model for an array of MTJs. The simulations are performed using SPICE and we solve the Landau Lifschitz Gilbert equation under the influence of exchange fields, spin torque effects and magnetostatic fields from the pinned layer and neighbouring MTJ elements. The exchange interactions and the spin torque effects are estimated via a two current model. It is observed that the neighbouring elements in a MTJ array increase the maximum current for switching an MTJ by 17.6%. © 2007 IEEE.