Convolutional Neural Networks (CNNs) are widely used due to their effectiveness in various AI applications such as object recognition, speech processing, etc., where the multiply-and-accumulate (MAC) operation contributes to ∼95% of the computation time. From the hardware implementation perspective, the performance of current CMOS-based MAC accelerators is limited mainly due to their von-Neumann architecture and corresponding limited memory bandwidth. In this way, silicon photonics has been recently explored as a promising solution for accelerator design to improve the speed and power-efficiency of the designs as opposed to electronic memristive crossbars. In this work, we briefly study recent silicon photonics accelerators and take initial steps to develop an open-source and adaptive crossbar architecture simulator for that. Keeping the original functionality of the MNSIM tool [1], we add a new photonic mode that utilizes the pre-existing algorithm to work with a photonic Phase Change Memory (pPCM) based crossbar structure. With inputs from the CNN's topology, the accelerator configuration, and experimentally-benchmarked data, the presented simulator can report the optimal crossbar size, the number of crossbars needed, and the estimation of total area, power, and latency.
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Photonic (computational) memories: tunable nanophotonics for data storage and computing
Abstract The exponential growth of information stored in data centers and computational power required for various data-intensive applications, such as deep learning and AI, call for new strategies to improve or move beyond the traditional von Neumann architecture. Recent achievements in information storage and computation in the optical domain, enabling energy-efficient, fast, and high-bandwidth data processing, show great potential for photonics to overcome the von Neumann bottleneck and reduce the energy wasted to Joule heating. Optically readable memories are fundamental in this process, and while light-based storage has traditionally (and commercially) employed free-space optics, recent developments in photonic integrated circuits (PICs) and optical nano-materials have opened the doors to new opportunities on-chip. Photonic memories have yet to rival their electronic digital counterparts in storage density; however, their inherent analog nature and ultrahigh bandwidth make them ideal for unconventional computing strategies. Here, we review emerging nanophotonic devices that possess memory capabilities by elaborating on their tunable mechanisms and evaluating them in terms of scalability and device performance. Moreover, we discuss the progress on large-scale architectures for photonic memory arrays and optical computing primarily based on memory performance.
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- NSF-PAR ID:
- 10335695
- Date Published:
- Journal Name:
- Nanophotonics
- Volume:
- 0
- Issue:
- 0
- ISSN:
- 2192-8606
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1515/nanoph-2022-0089
