Conference Paper

Long period grating coated with high refractive index layer

Department of Energy Engineering, Università degli Studi del Sannio, Benevento, Campania, Italy
DOI: 10.1109/WFOPC.2005.1462157 Conference: Fibres and Optical Passive Components, 2005. Proceedings of 2005 IEEE/LEOS Workshop on
Source: IEEE Xplore


In this work, we theoretically and experimentally investigated the cladding modes re-organization in high refractive index coated long period gratings (LPGs), focusing the attention on the influence on the refractive index sensitivity. When azimuthally symmetric nano-scale HRI coatings are deposited along LPGs devices, a significant modification of the cladding modes distribution occurs, depending on the layer features (refractive index and thickness) and on the surrounding refractive index. In particular, if these parameters are properly chosen, the transition between cladding modes and overlay modes occurs. Here, numerical and experimental results on the effect of the modes transition surrounding refractive index (SRI) sensitivity are presented.

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