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.
@article{arxiv.2007.12357,
title = {Ultra-low Power Domain Wall Device for Spin-based Neuromorphic Computing},
author = {Durgesh Kumar and Chung Hong Jing and Chan JianPeng and Tianli Jin and Lim Sze Ter and Rachid Sbiaa and S. N. Piramanayagam},
journal= {arXiv preprint arXiv:2007.12357},
year = {2020}
}