# Demonstration of Superconducting Optoelectronic Single-Photon Synapses

arXiv: https://arxiv.org/abs/2204.09665 · HTML: https://mlsanity.com/paper/2204.09665/

## Key facts

- No citing papers in the map yet (data through 14 Oct 2026).
- Builds on 11 of its 59 references that are in the map.
- First posted on arXiv 20 Apr 2022.

## Builds on (most cited first, 11 of 11)

- [Language Models are Few-Shot Learners](https://mlsanity.com/paper/2005.14165/) (2020)
- [Deep Learning Scaling is Predictable, Empirically](https://mlsanity.com/paper/1712.00409/) (2017)
- [Deep Learning in Spiking Neural Networks](https://mlsanity.com/paper/1804.08150/) (2018)
- [SuperSpike: Supervised learning in multi-layer spiking neural networks](https://mlsanity.com/paper/1705.11146/) (2017)
- [Neuromorphic electronic circuits for building autonomous cognitive systems](https://mlsanity.com/paper/1403.6428/) (2014)
- [Criticality in the brain: A synthesis of neurobiology, models and cognition](https://mlsanity.com/paper/1707.05952/) (2017)
- [The importance of space and time in neuromorphic cognitive agents](https://mlsanity.com/paper/1902.09791/) (2019)
- [Optoelectronic Intelligence](https://mlsanity.com/paper/2010.08690/) (2020)
- [Circuit designs for superconducting optoelectronic loop neurons](https://mlsanity.com/paper/1805.01947/) (2018)
- [Fluxonic Processing of Photonic Synapse Events](https://mlsanity.com/paper/1904.02807/) (2019)
- [An active dendritic tree can mitigate fan-in limitations in superconducting neurons](https://mlsanity.com/paper/2107.05777/) (2021)

## Abstract (arXiv)

Superconducting optoelectronic hardware is being explored as a path towards artificial spiking neural networks with unprecedented scales of complexity and computational ability. Such hardware combines integrated-photonic components for few-photon, light-speed communication with superconducting circuits for fast, energy-efficient computation. Monolithic integration of superconducting and photonic devices is necessary for the scaling of this technology. In the present work, superconducting-nanowire single-photon detectors are monolithically integrated with Josephson junctions for the first time, enabling the realization of superconducting optoelectronic synapses. We present circuits that perform analog weighting and temporal leaky integration of single-photon presynaptic signals. Synaptic weighting is implemented in the electronic domain so that binary, single-photon communication can be maintained. Records of recent synaptic activity are locally stored as current in superconducting loops. Dendritic and neuronal nonlinearities are implemented with a second stage of Josephson circuitry. The hardware presents great design flexibility, with demonstrated synaptic time constants spanning four orders of magnitude (hundreds of nanoseconds to milliseconds). The synapses are responsive to presynaptic spike rates exceeding 10 MHz and consume approximately 33 aJ of dynamic power per synapse event before accounting for cooling. In addition to neuromorphic hardware, these circuits introduce new avenues towards realizing large-scale single-photon-detector arrays for diverse imaging, sensing, and quantum communication applications.