9 May 2012 Polarization dependency in metal oxide coated tilted FBG refractometers
Author Affiliations +
Abstract
Tilted fiber Bragg gratings (TFBGs) present a refractive index modulation blazed by a few degrees in the plane perpendicular to the optical fiber axis. This results in two kinds of couplings: self-backward coupling of the core mode and numerous backward couplings between the core mode and the cladding modes. TFBG transmitted amplitude spectra are therefore characterized by several tens of cladding mode resonances that possess their own sensitivity to the surrounding refractive index (SRI). TFBGs naturally allow the realization of refractometers accurate to 10-4 RIU (refractive index unit) in the SRI range between 1.33 and 1.45 (refractive index of silica). In this work, we demonstrate that a dense thin film of zinc oxide, a high refractive index material (n=1.9), deposited by RF sputtering in two steps, on the TFBGs tightly modifies their transmitted amplitude spectra. While the wavelength difference between orthogonally polarized modes in nude TFBGs remains within a few picometers, the association of a nanoscale metal oxide coating increases this difference up to 500 picometers. This results in two main assets: the sensitivity is extended to SRI values above 1.45 while the strong polarization dependency makes the demodulation process easier.
© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Jean-Michel Renoirt, Jean-Michel Renoirt, Chao Zhang, Chao Zhang, Marc Debliquy, Marc Debliquy, Christophe Caucheteur, Christophe Caucheteur, Marie-Georges Olivier, Marie-Georges Olivier, Patrice Mégret, Patrice Mégret, } "Polarization dependency in metal oxide coated tilted FBG refractometers", Proc. SPIE 8439, Optical Sensing and Detection II, 84392H (9 May 2012); doi: 10.1117/12.922262; https://doi.org/10.1117/12.922262
PROCEEDINGS
6 PAGES


SHARE
Back to Top