Synaptic weighting in single flux quantum neuromorphic computing

Published

January 22, 2020

Author(s)

Michael L. Schneider, Christine A. Donnelly, Ian W. Haygood, Alex Wynn, Stephen E. Russek, Manuel C. Castellanos Beltran, Paul D. Dresselhaus, Peter F. Hopkins, Matthew R. Pufall, William H. Rippard

Abstract

Josephson junctions act as a natural spiking neuron-like device for neuromorphic computing. By leveraging the advances recently demonstrated in digital single flux quantum (SFQ) circuits and using recently demonstrated magnetic Josephson junction (MJJ) synaptic circuits, there is potential to make rapid progress in SFQ-based neuromorphic computing. Here we demonstrate the basic functionality of a synaptic circuit design that takes advantage of the adjustable critical current demonstrated in MJJs and implement a synaptic weighting element. The devices were fabricated with a restively shunted Nb/Al_Ox-Al/Nb process that did not include MJJs. Instead, the MJJ functionality was tested by making multiple circuits and varying the critical current, but not the external shunt resistance, of the oxide Josephson junction that represents the MJJ. Experimental measurements and simulations of the fabricated circuits are in good agreement.

Citation

Scientific Reports

Volume

10

Pub Type

Journals

Download Paper

https://doi.org/10.1038/s41598-020-57892-0

Local Download

Keywords

neuromorphic, spintronics, single flux quantum, Josephson junctions, circuits, SFQ-based neuromorphic computing, MJJ functionality

Citation

Schneider, M. , Donnelly, C. , Haygood, I. , Wynn, A. , Russek, S. , Castellanos, M. , Dresselhaus, P. , Hopkins, P. , Pufall, M. and Rippard, W. (2020), Synaptic weighting in single flux quantum neuromorphic computing, Scientific Reports, [online], https://doi.org/10.1038/s41598-020-57892-0 (Accessed April 25, 2024)