Theoretical Investigation of Double Barrier Perpendicular Anisotropy Magnetic Tunnel Junction

STT-MRAM has emerged as one of the most promising candidates for future universal memory technology. The biggest challenges in this area are high switching current densities, large switching delays and low thermal stability. In this paper, we propose a device structure based on a double barrier perpendicular magnetic anisotropy magnetic tunnel junction and investigate it theoretically using detailed micromagnetic simulations and first principles stability analysis and TMR calculation. We report large improvements in switching current densities at constant switching delays without compromising thermal stability of the device. We show a large increase in stability of AP and P states of the device compared with single barrier junctions. TMR is also seen to improve with the possibility of an enhanced TMR effect that can be tuned by altering the free layer thickness.