HIGH-TC JOSEPHSON NEURONS AND SYNAPSES: TOWARDS ULTRAFAST AND ENERGY EFFICIENT SUPERCONDUCTING NEUROMORPHIC COMPUTING

Introduction

We aim at realizing a novel class of high-temperature Josephson junctions (JJs) that behave as artificial neurons and synapses. These JJs will enable a new neuromorphic computing paradigm, in which neural networks are much faster, more energy efficient, and compact than with non-superconducting approaches, and possess novel capabilities (combined sensitivity to light, magnetic, and electric fields).

Long-term Vision

Via these rupture ingredients, JOSEPHINE will dramatically enhance the impact of neuromorphics on its broad range of projected applications:

1. Artificial intelligence (where it would allow supercomputer-level processors at a fraction of the environmental cost)
2. Control of autonomous vehicles
3. Internet of Things
4. Novel medical applications

That constitutes the long-term vision for the science we propose.

Strategies for Realization

To reach that goal, we will use different strategies to realize high-Tc Josephson junctions whose weak-links are active and can be changed "in operando" by external stimuli. Those strategies include:

• "Weak links" modified by a nanoscale redox reaction
• The motion of domain walls in a ferromagnet
• Locally doping a graphene or a 2D semiconductor

Implementation and Testing

Once realized, these JJs will be implemented and tested in neural networks to demonstrate their performance and their transformative effect on neuromorphics.

Multidisciplinary Approach

The proposed strategy exploits recent breakthrough results of the partners (physical effects that will be implemented) and synergizes their complementary expertise via a multidisciplinary approach that marries traditionally distant disciplines:

• Neural network engineering
• Superconducting electronics
• Various facets of solid-state physics (superconductivity, magnetism, Dirac materials, and electrochemistry)