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arXiv · 2409.06286

Mimicking synaptic plasticity with wedged Pt/Co/Pt spin-orbit torque device

Shiwei Chen·Mishra Rahul·Huanjian Chen·Hyunsoo Yang·Xuepeng Qiu
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Abstract

We fabricated a wedge-shaped Pt/Co/Pt device with perpendicular magnetic anisotropy and manifested that the Co magnetization can be solely switched by spin-orbit torque without any magnetic field. Similar to the synaptic weight, we observed that the state of Co magnetization (presented by the anomalous Hall resistance RH) of the wedged Pt/Co/Pt device can be tuned continuously with a large number of nonvolatile levels by applied pulse currents. Furthermore, we studied the synaptic plasticity of the wedged Pt/Co/Pt device, including the excitatory postsynaptic potentials or inhibitory postsynaptic potentials and spiking-time-dependent plasticity. The work elucidates the promise of the wedged Pt/Co/Pt device as a candidate for a new type of artificial synaptic device that is induced by a spin current and paves a substantial pathway toward the combination of spintronics and synaptic devices.

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Shiwei Chen, Mishra Rahul, Huanjian Chen, Hyunsoo Yang, Xuepeng Qiu. 2024-09-10. Mimicking synaptic plasticity with wedged Pt/Co/Pt spin-orbit torque device. https://doi.org/10.1088/1361-6463/ac33d9

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