Scaling Photonic Computing Across Device, Architecture, and System Levels

Abstract: Photonics information processing strategies offer the unique ability to perform analog computation with ultra-low latency and high efficiency. However, designing compact and reconfigurable photonic architectures which scale well at the architecture and system level is a challenge. The combination of bistable optical materials (such as phase-change materials like Ge2Sb2Te5 and Sb2Se3) and integrated photonics is a promising approach which enables nonvolatile optical memory on-chip with low drift, compact footprint, and high-speed readout. This talk will first present our work developing robust and scalable photonic memories using phase-change and magneto-optic materials (Ce:YIG) for photonic “in-memory” computing techniques. I will then discuss our recent theoretical and experimental results using coherent photonic crossbar arrays to implement large-scale matrix-matrix multiplication. Finally, I will present a new approach to enable distributed photonic computing over fiber without costly electrical-to-optical or analog-to-digital conversions.

BIO: Dr. Nathan Youngblood, William Kepler Whiteford Faculty Fellow and Associate Professor of Electrical and Computer Engineering, joined the University of Pittsburgh in September 2019. As a postdoctoral researcher at the University of Oxford from 2017 to 2019, he developed phase-change optical systems and photonic architectures for non-von Neumann computing. In 2016, he received a PhD in Electrical Engineering from the University of Minnesota where his research focused on integrating 2D materials with silicon photonics for optoelectronic applications. Nathan is the recipient of the NSF CAREER and AFOSR Young Investigator Awards, as well as the Friedrich Wilhelm Bessel Research Award from the Alexander von Humboldt Foundation for his innovations in optical computing and photonic memory technologies. His work has been published in leading journals such as Nature, Nature Photonics, and Science Advances, and featured in popular news outlets such as The Times, London and the Daily Mail.