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arXiv · 1304.4442

Resonant THz sensor for paper quality monitoring using THz fiber Bragg gratings

Guofeng Yan·Andrey Markov·Yasser Chinifooroshan·Saurabh M. Tripathi·Wojtek J. Bock·Maksim Skorobogatiy
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Abstract

We report fabrication of THz fiber Bragg gratings (TFBG) using CO2 laser inscription on subwavelength step-index polymer fibers. A fiber Bragg grating with 48 periods features a ~4 GHz-wide stop band and ~15 dB transmission loss in the middle of a stop band. The potential of such gratings in design of resonant sensor for monitoring of paper quality is demonstrated. Experimental spectral sensitivity of the TFBG-based paper thickness sensor was found to be ~ -0.67 GHz / 10 um. A 3D electromagnetic model of a Bragg grating was used to explain experimental findings.

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Guofeng Yan, Andrey Markov, Yasser Chinifooroshan, Saurabh M. Tripathi, Wojtek J. Bock, Maksim Skorobogatiy. 2013-05-25. Resonant THz sensor for paper quality monitoring using THz fiber Bragg gratings. https://doi.org/10.1364/ol.38.002200

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