Spin-orbit torque magnetic tunnel junction based on 2-D materials: Impact of bias-layer on device performance

Two-dimensional (2D) material-based Spin-orbit torque (SOT) Magnetic tunnel junction (MTJ) has drawn a lot of research interest due to its potential for low power logic and memory applications. In this study, we employed a Bias-layer (BL) on top of the Topological insulator (TI) based SOT-MTJ structure to achieve field-free deter-ministic switching. A systematic micromagnetic simulation is carried out to examine the impact of variations in the BL-width (BW) and BL-distance (BLD) from the Free-layer (FL) on the performance parameters of the device. The stray field produced by the BL has a non-uniform profile; it declines with increase in BLD from the FL and improves with as BW increases. We demonstrate that by engineering the BLD and BW, the critical current density reduces to 3.9 x 109 A/m2, switching speed improves by 0.14 ns and power dissipation density reduces to 6.98 x 1014 Watt/m3as compared to the conventional SOT-MTJ with an external magnetic field of 100 mH.