Ultra-low Power Domain Wall Device for Spin-based Neuromorphic Computing

TL;DR

This paper demonstrates ultra-low energy domain wall motion in spintronic devices, enabling highly energy-efficient neuromorphic computing components with minimal power consumption at nanometer scales.

Contribution

It introduces a novel low-current domain wall motion technique using tailored beta-W spin Hall material, achieving significant energy reduction for neuromorphic applications.

Findings

Domain wall motion at current densities as low as 1E6 A/m2

Energy consumption of 0.4 aJ/bit for 20 nm bits

Reduced pinning fields and current densities by a factor of 10,000

Abstract

Neuromorphic computing (NC) is gaining wide acceptance as a potential technology to achieve low-power intelligent devices. To realize NC, researchers investigate various types of synthetic neurons and synaptic devices such as memristors and spintronic domain wall (DW) devices. In comparison, DW-based neurons and synapses have potentially higher endurance. However, for realizing low-power devices, DW motion at low energies - typically below pJ/bit - are needed. Here, we demonstrate domain wall motion at current densities as low as 1E6 A/m2 by tailoring the beta-W spin Hall material. With our design, we achieve ultra-low pinning fields and current density reduction by a factor of 10000. The energy required to move the domain wall by a distance of about 20 micrometers is 0.4 fJ, which translates into energy consumption of 0.4 aJ/bit for a bit-length of 20 nm. With a meander domain wall device configuration, we have established a controlled DW motion for synapse applications and have shown the direction to make ultra-low energy spin-based neuromorphic elements.