On-chip photonic synapse

作者：Zengguang Cheng, Carlos Rı́os, Wolfram H. P. Pernice, C. David Wright, Harish Bhaskaran · 发表于：Science Advances · 年份：2017 · DOI：10.1126/sciadv.1700160 · 被引用次数：598 · 研究领域：Advanced Memory and Neural Computing、Neuroscience and Neural Engineering、Neural dynamics and brain function

The search for new "neuromorphic computing" architectures that mimic the brain's approach to simultaneous processing and storage of information is intense. Because, in real brains, neuronal synapses outnumber neurons by many orders of magnitude, the realization of hardware devices mimicking the functionality of a synapse is a first and essential step in such a search. We report the development of such a hardware synapse, implemented entirely in the optical domain via a photonic integrated-circuit approach. Using purely optical means brings the benefits of ultrafast operation speed, virtually unlimited bandwidth, and no electrical interconnect power losses. Our synapse uses phase-change materials combined with integrated silicon nitride waveguides. Crucially, we can randomly set the synaptic weight simply by varying the number of optical pulses sent down the waveguide, delivering an incredibly simple yet powerful approach that heralds systems with a continuously variable synaptic plasticity resembling the true analog nature of biological synapses.