The parallelism of optics and the miniaturization of optical components using nanophotonic structures, such as metasurfaces, present a compelling alternative to electronic implementations of convolutional neural networks. The lack of a low-power optical nonlinearity, however, requires slow and energy-inefficient conversions between the electronic and optical domains. Here, we design an architecture that utilizes a single electrical to optical conversion by designing a free-space optical frontend unit that implements the linear operations of the first layer with the subsequent layers realized electronically. Speed and power analysis of the architecture indicates that the hybrid photonic–electronic architecture outperforms a fully electronic architecture for large image sizes and kernels. Specifically, we demonstrate system-level photonic advantage over a purely digital one. We also explore the ways the nonlinearity can be implemented in optical domain and analyze the performance of a degenerate cavity for nonlinear image processing.
Biography:
Prof. Arka Majumdar is an Associate Professor in the departments of Electrical and Computer Engineering and Physics at the University of Washington (UW). He received B. Tech. from IIT-Kharagpur (2007) where he was honored with the President’s Gold Medal. He completed his MS (2009) and Ph.D. (2012) in Electrical Engineering at Stanford University. He spent one year at the University of California Berkeley (2012-13) and then in Intel Labs (2013-14) as postdoc before joining UW. His research interests include developing a hybrid nanophotonic platform using emerging material systems for optical information science imaging and microscopy. Prof. Majumdar is the recipient of multiple Young Investigator Awards from the AFOSR (2015) NSF (2019) ONR (2020) and DARPA (2021) Intel early career faculty award (2015) Amazon Catalyst Award (2016) Alfred P. Sloan fellowship (2018) UW college of engineering outstanding junior faculty award (2020) iCANX Young Scientist Award (2021) and IIT-Kharagpur Young Alumni Achiever Award (2022). He is co-founder and technical advisor of Tunoptix a startup commercializing software defined meta-optics.