DMI Influence on the Integration, Leakage, and Threshold Property of Domain Wall Based Neurons

Abstract

Interest in spintronic devices based on the motion of domain walls (DWs) has been growing rapidly as they are seen as potential components of neuromorphic information processing systems. In this article, we propose a leaky integrate-and-fire (LIF) neuron based on DW motion through spin orbit torque (SOT), in which the intrinsic leaking is achieved, thanks to the realization of an anisotropy gradient along the track. In particular, we studied the influence of Dzyaloshinskii-Moriya interaction (DMI) on the property of the neuron, showing how it affects the integration and leaking property of this type of structure. Moreover, we show how it offers a way to tune the leakage velocity of the DW, demonstrating how important DMI is in this kind of structure, showing that it plays a key role in regulating the SOT efficiency and the leaking speed. In addition, we exploited the voltage-controlled magnetic anisotropy (VCMA) effect to implement the neuron threshold. Finally, we show how all these ingredients can be combined together into a single device.