Monolithic Silicon Photonic Architecture for Training Deep Neural Networks with Direct Feedback Alignment. - Matthew J. Filipovich; Zhimu Guo; Mohammed Al-Qadasi; Bicky A. Marquez; Hugh D. Morison; Volker J. Sorger; Paul R. Prucnal; Sudip Shekhar; Bhavin J. Shastri (CoRR, 2021)