Spiking Dynamics in Dual Free Layer Perpendicular Magnetic Tunnel Junctions

Louis Farcis; Bruno Teixeira; Philippe Talatchian; David Salomoni; Ursula Ebels; Stéphane Auffret; Bernard Dieny; Frank Mizrahi; Julie Grollier; Ricardo Sousa; Liliana Buda-Prejbeanu

arXiv · 2309.07535

Spiking Dynamics in Dual Free Layer Perpendicular Magnetic Tunnel Junctions

Louis Farcis·Bruno Teixeira·Philippe Talatchian·David Salomoni·Ursula Ebels·Stéphane Auffret·Bernard Dieny·Frank Mizrahi·Julie Grollier·Ricardo Sousa·Liliana Buda-Prejbeanu

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Abstract

Spintronic devices have recently attracted a lot of attention in the field of unconventional computing due to their non-volatility for short and long term memory, non-linear fast response and relatively small footprint. Here we report how voltage driven magnetization dynamics of dual free layer perpendicular magnetic tunnel junctions enable to emulate spiking neurons in hardware. The output spiking rate was controlled by varying the dc bias voltage across the device. The field-free operation of this two terminal device and its robustness against an externally applied magnetic field make it a suitable candidate to mimic neuron response in a dense Neural Network (NN). The small energy consumption of the device (4-16 pJ/spike) and its scalability are important benefits for embedded applications. This compact perpendicular magnetic tunnel junction structure could finally bring spiking neural networks (SNN) to sub-100nm size elements.

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Louis Farcis, Bruno Teixeira, Philippe Talatchian, David Salomoni, Ursula Ebels, Stéphane Auffret, Bernard Dieny, Frank Mizrahi, Julie Grollier, Ricardo Sousa, Liliana Buda-Prejbeanu. 2023-09-14. Spiking Dynamics in Dual Free Layer Perpendicular Magnetic Tunnel Junctions. https://arxiv.org/abs/2309.07535

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