Search

The spin transfer torque assisted magnetization switching in a pentalayer nanopillar device is theoretically studied for different biasing configurations. The magnetization switching time is calculated for three different configurations (standard(no biasing), pinned layer biasing and free layer biasing), by numerically solving the governing dynamical Landau–Lifshitz–Gilbert–Slonczewski (LLGS) equation. The corresponding switching time for an applied current density of 3 × 10 11 Am − 2 is about 0.296 ns, 0.195 ns, and 0.108 ns respectively. Pinned layer biasing and free layer biasing increase the magnetization switching speed significantly. Reduction of switching time in the pinned layer biasing is due to the enhancement of spin transfer torque, whereas in the free layer biasing it is due to an additional magnetic torque which arises due to an applied magnetic field. The fastest magnetization switching is achieved for the free layer biasing configuration. [ABSTRACT FROM AUTHOR]

Abstract: Magnetization switching dynamics in FePt/Au/FePt nanopillar, induced by spin-transfer torque is investigated by solving the Landau–Lifshitz–Gilbert–Slonczewski equation. The switching of magnetization occurs in the device, above a threshold current density of , which agrees well with the previously reported experimentally measured value. This further reduces to , when there is interface anisotropy in the free FePt layer, whose presence has been identified recently through scanning tunneling microscopy images and X-ray magnetic circular dichroism. The interface anisotropy also reduces the switching time from 15.59ps to 9.56ps when the device having a free FePt layer of thickness 1.5nm is operated with a current density of . [Copyright &y& Elsevier]

Abstract: Spin-transfer induced ultrafast precessional switching of magnetization in a Co/Cu/Co nanopillar device is studied. Micromagnetic calculations show that precessional magnetization switching occurs above a threshold current. The presence of interface uniaxial anisotropy in the Co-thin film free layer influences heavily the current and the energy required to initiate the switching in the device, and the speed of the precessional switching. The threshold current and the precessional switching time are significantly reduced by this effect. [Copyright &y& Elsevier]

Abstract: Precessional switching of magnetization in CoPt and FePt nanofilms is investigated by solving the Landau–Lifshitz–Gilbert (LLG) equation analytically and numerically. Switching in these films occurs only above a critical value of the magnetic field, and it further depends on the magnetocrystalline anisotropy and saturation magnetization of the film. The presence of magnetic surface anisotropy in these films reduces the switching time significantly. Also, the switching time in the case of Pt-alloys of Co and Fe is low compared to that in the case of pure Co and Fe films. [Copyright &y& Elsevier]