Full-Range Ultrasensitive Fiber-Optic Hydrogen Detection via Twin Vernier Amplification and Lightweight CNN.

Authors

Chaofan Li, Yinuo Yan, Lufeng Wang, Jiashuo Zhang, Yingxuan Liu, Yong Zhao

Published in

ACS sensors. Aug 09, 2026. Epub Aug 09, 2026.

Abstract

Reliable hydrogen monitoring requires sensors that combine high sensitivity, wide dynamic range, and resistance to environmental interference. Here, we report a monolithically integrated dual-Fabry-Pérot interferometer (dual-FPI) fiber-optic hydrogen sensor that couples twin Vernier spectral amplification with a lightweight dual-branch fusion convolutional neural network (DBF-CNN). The sensor incorporates a polydimethylsiloxane (PDMS)-filled temperature reference cavity and a PDMS/Pd-WO3 hydrogen-sensitive cavity on a single fiber, enabling intrinsic temperature compensation and humidity-insensitive detection without external reference devices. Digital twin Vernier amplification provides an approximately 10-fold sensitivity enhancement, giving a sensitivity of -62.989 nm/% and a limit of detection of 5.33 ppm. To resolve the wavelength ambiguity imposed by the free spectral range (FSR), we combine physics-guided spectral data augmentation with a lightweight DBF-CNN regression model to achieve end-to-end 0-100% volume fraction hydrogen concentration inversion, with an R2 of 0.999443 and a root mean square error (RMSE) of 0.682%. This integrated sensing strategy simultaneously addresses sensitivity, detection range, and environmental cross-sensitivity, offering a compact approach for fiber-optic hydrogen safety monitoring.

PMID:
42571614
Bibliographic data and abstract were imported from PubMed on 09 Aug 2026.

Read full publication at:
Please sign in to see all details.

Stats

1-terrible, 9-excellent. How would you rate this publication? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.