Micromagnetic Simulation of Spin Transfer Torque Switching of Full-Heusler Co2FeAl0.5Si0.5 Alloy Thin Elliptical Disc

We report micromagnetic simulation of spin transfer torque (STT) switching of a thin elliptical disc made of full-Heusler Co2FeAl0.5Si0.5 alloy. The STT results in switching the direction of initial magnetization of the disc to a new state based on the spin-polarization factor (ƞ) of the material and magnitude of current density (J) applied. The value of J required for magnetization switching need to be reduced in the order of 106 A/cm2. In our simulation we obtained 3 × 105 A/cm2 as the critical current density (Jc) required for complete magnetization switching of the disc. We analyzed the effect of ƞ on magnetization switching time by reducing the value of ƞ by 0.10 from the actual value of 0.76. The decrement in ƞ results in the increment of time taken to switch the direction of magnetization. The change in switching time for variable disc thickness was also studied. This simulation result holds a key factor in the study of STT switching in spin-valve nanopillar.