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The manipulation of magnetization by an electric current can be obtained thanks to the spin-transfer torque (STT) phenomenon. The two main mechanisms that give rise to this phenomenon are the spin filtering torque (SFT) and the spin-orbit torque (SOT). The former is obtained in multilayer systems by passing a spin-polarized current through the multilayers, whereas the latter is achieved through a direct transfer of angular momentum from the crystal lattice through the spin–orbit interaction. In this work, we study the influence of these two mechanisms on the magnetization dynamics of a three-terminal spin-torque oscillator. The device is composed of either a spin-valve (SV) or a magnetic tunnel junction (MTJ) on top of a Pt wire. The system can be excited either by SFT or by SOT depending on whether the current is applied through the magnetic structure (SV or MTJ) or through the Pt wire. Finally, each device is compared to a reference sample where the Pt wire is replaced by a Cu wire. Therefore, no SOT is expected in this second set of devices. In this presentation, we compare the different types of devices in order to understand the transport in the three terminal devices and study the role of the different mechanisms (SFT and STT) on the magnetization dynamics. Finally, we propose a method to compare the spin transfer efficiency of the two mechanisms on a single device.
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