Effect of macro-bending on resonant wavelength and intensity of long-period gratings in photonic crystal fiber

Department of Chemical Engineering & Materials Science, Stevens Institute of Technology, Hoboken, New Jersey, United States
Optics Express (Impact Factor: 3.53). 03/2007; 15(4):1804-10. DOI: 10.1364/OE.15.001804
Source: PubMed

ABSTRACT We report the spectral characteristics of CO(2)-laser inscribed long-period gratings (LPGs) in endlessly single mode photonic crystal fiber (PCF) subject to macro-bending. The coupling modes as a result of bending were studied by examining the shifts of resonant wavelengths, the splits of attenuation bands, and the variation in coupling strength of the transmission spectra. A bending coefficient of ~ 27.9 nm.m was determined in the PCF at 180 degrees rotational orientation relative to the point of laser inscription in the curvature range from 2.6 m(-1) to 3.5 m(-1). Compared with conventional fiber LPGs fabricated using the same method, the PCF-based LPGs possess higher sensitivity both to bending and orientation, making them promising for sensor applications.

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Available from: Henry Du, Apr 14, 2015
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