LCAP: Population-Informed Latent Chip Adaptation from Few Output Probes for Photonic Neural Networks

Tianyu Gao; Guantian Zheng

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arXiv · 2609.16823

LCAP: Population-Informed Latent Chip Adaptation from Few Output Probes for Photonic Neural Networks

Tianyu Gao·Guantian Zheng

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Abstract

Photonic neural networks (PNNs) offer efficient analog inference, but parameters optimized under ideal device models can degrade after fabrication, creating a persistent simulation-to-hardware (sim-to-real) gap. When many identically designed chips are deployed, calibrating each device from scratch compounds this cost. We propose Latent Chip Adaptation from Probes (LCAP), a population-informed framework that decomposes hardware adaptation into a transferable population correction and probe-inferred latent personalization. LCAP first learns a shared correction from 80 historical chips, then extracts a low-dimensional correction space from device-specific refinements. At deployment, 32 fixed unlabeled output probes infer an unseen chip's latent correction coordinates, enabling feed-forward personalization without target-device optimization. On a three-layer 64-mode MZI simulator with phase variation, beam-splitter errors, quantization, and crosstalk, accuracy improves from 80.4147% under direct deployment to 92.6860% after shared calibration and 93.3617% with LCAP. LCAP improves 27/30 unseen chips and raises worst-device accuracy from 89.18% to 90.54%.

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BibTeX RIS

Tianyu Gao, Guantian Zheng. 2026-09-15. LCAP: Population-Informed Latent Chip Adaptation from Few Output Probes for Photonic Neural Networks. https://arxiv.org/abs/2609.16823

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