Physical neural networks using sharpness-aware training.

Journal: Nature communications
Published Date:

Abstract

Recent advances in AI are pushing the limits of traditional hardware, making physical neural networks (PNNs) a promising alternative. However, training PNNs remains challenging: in silico training suffers from model-reality mismatch, while in situ training produces device-specific models that do not transfer across fabrication variations. Both approaches are further compromised by post-deployment perturbations, such as thermal drift or misalignment, which invalidate trained models and require retraining. We address these challenges through sharpness-aware training (SAT), inspired by sharpness-aware minimization, which links loss landscape geometry to generalization. We establish a connection between loss landscape sharpness and robustness in physical systems and leverage it to improve PNN training. SAT is compatible with both in silico and in situ settings: it mitigates model-reality gaps, enables cross-device transfer, and provides strong resilience to post-deployment perturbations without retraining. We demonstrate SAT across three PNN platforms and multiple tasks, including classification, compression, reconstruction, and generation, showing its broad applicability.

Authors

  • Tengji Xu
    Department of Electronic Engineering, The Chinese University of Hong Kong, Hong Kong SAR, China.
  • Zeyu Luo
    Chongqing Key Laboratory of Vector Insects.
  • Shaojie Liu
    College of Foreign Languages, Shaanxi Xueqian Normal University, Xian, Shaanxi 710100, China.
  • Li Fan
    Department of Radiology, Second Affiliated Hospital of Naval Medical University, Shanghai, China.
  • Qiarong Xiao
    Department of Electronic Engineering, The Chinese University of Hong Kong, Hong Kong SAR, China.
  • Benshan Wang
    Department of Electronic Engineering, The Chinese University of Hong Kong, Hong Kong SAR, China.
  • Dongliang Wang
    ChosenMed Technology (Beijing) Co., Ltd., Beijing 100176, China.
  • Chaoran Huang
    Department of Electronic Engineering, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.

Keywords

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