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arXiv · 2403.00045

An All-Optical General-Purpose CPU and Optical Computer Architecture

Michael Kissner·Leonardo Del Bino·Felix Päsler·Peter Caruana·George Ghalanos
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Abstract

Energy efficiency of electronic digital processors is primarily limited by the energy consumption of electronic communication and interconnects. The industry is almost unanimously pushing towards replacing both long-haul, as well as local chip interconnects, using optics to drastically increase efficiency. In this paper, we explore what comes after the successful migration to optical interconnects, as with this inefficiency solved, the main source of energy consumption will be electronic digital computing, memory and electro-optical conversion. Our approach attempts to address all these issues by introducing efficient all-optical digital computing and memory, which in turn eliminates the need for electro-optical conversions. Here, we demonstrate for the first time a scheme to enable general purpose digital data processing in an integrated form and present our photonic integrated circuit (PIC) implementation. For this demonstration we implemented a URISC architecture capable of running any classical piece of software all-optically and present a comprehensive architectural framework for all-optical computing to go beyond.

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Michael Kissner, Leonardo Del Bino, Felix Päsler, Peter Caruana, George Ghalanos. 2024-02-29. An All-Optical General-Purpose CPU and Optical Computer Architecture. https://doi.org/10.1109/jlt.2024.3458459

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