Voltage-controlled skyrmion-based artificial synapse in a synthetic antiferromagnet

TL;DR

This paper introduces a low-energy spintronic memristor using synthetic antiferromagnets and skyrmions, enabling neuromorphic computing with high efficiency and tunable synaptic weights.

Contribution

It proposes a novel ultralow-dissipation spintronic synapse based on skyrmion manipulation in a synthetic antiferromagnet with electric field control.

Findings

Achieved resistance variation through skyrmion size control

Demonstrated ultralow energy consumption of 0.3 fJ per operation

Paved the way for ultralow power neuromorphic computing

Abstract

Spintronics exhibits significant potential in neuromorphic computing system with high speed, high integration density, and low dissipation. In this letter, we propose an ultralow-dissipation spintronic memristor composed of a synthetic antiferromagnet (SAF) and a piezoelectric substrate. Skyrmions/skyrmion bubbles can be generated in the upper layer of SAF with weak anisotropy energy (Ea). With a weak electric field on the heterostructure, the interlayer antiferromagnetic coupling can be manipulated, giving rise to a continuous transition between a large skyrmion bubble and a small skyrmion. This thus induces the variation of the resistance of a magnetic tunneling junction. The synapse based on this principle may manipulate the weight in a wide range at a cost of a very low energy consumption of 0.3 fJ. These results pave a way to ultralow power neuromorphic computing applications.