Spike-timing-dependent-plasticity learning in a planar magnetic domain wall artificial synapsis

TL;DR

This paper demonstrates a simplified spin memristor based on Co/Pt multilayers that emulates synaptic plasticity and spike-timing-dependent plasticity (STDP), crucial for future neuromorphic systems, by controlling resistance with magnetic pulses.

Contribution

It introduces a novel magnetic device that exhibits plasticity and STDP, with detailed magnetic mechanisms elucidated through microscopy and transport measurements.

Findings

Demonstrated STDP in a magnetic spin memristor

Identified threshold behavior for magnetization reversal

Achieved continuous resistance states linked to magnetic configurations

Abstract

Future neuromorphic architectures will require millions of artificial synapses, making understanding the physical mechanisms behind their plasticity functionalities mandatory. In this work, we propose a simplified spin memristor, where the resistance can be controlled by magnetic field pulses, based on a Co/Pt multilayer with perpendicular magnetic anisotropy as a synapsis emulator. We demonstrate plasticity and spike time dependence plasticity (STDP) in this device and explored the underlying magnetic mechanisms using Kerr microscopy imaging and Hall magneto-transport measurements. A well-defined threshold for magnetization reversal and the continuous resistance states associated with the micromagnetic configuration are the basic properties allowing plasticity and STDP learning mechanisms in this device.