Spectral Behavior in Nano-Coated Tilted Fiber Bragg Gratings: Effect of Thickness and External Refractive Index

• Published in: IEEE photonics technology letters Vol. 19; no. 24; pp. 2051 - 2053
• Main Authors: Paladino, D., Cusano, A., Pilla, P., Campopiano, S., Caucheteur, C., Megret, P.
• Format: Journal Article
• Language: English
• Published: New York IEEE 15-12-2007; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Couplings; Dip coating; Fiber gratings; Fiber lasers; Fiber optics; Fiber-optic refractometers; Fibers; nano-coatings; Nanomaterials; Nanostructure; Optical fiber devices; Optical fibers; Optical films; Optical refraction; Refractive index; Refractivity; Resonance; Spectra; Spectral analysis; tilted fiber Bragg gratings (TFBGs)
• ISSN: 1041-1135; 1941-0174
• DOI: 10.1109/LPT.2007.909627

This work reports on the experimental investigation of the spectral effects induced by uniform high refractive index nano-coatings deposited on weakly tilted fiber Bragg gratings (TFBGs). To this aim, weakly TFBGs with different tilt angles were fabricated and then coated with thin overlays of syndiotactic polystyrene. Automated dip coating technique was used to obtain ring-shaped coatings with thickness ranging in hundreds of nanometers. The transmission spectra of the obtained devices were collected in order to outline the effects of thickness, tilt angle, and surrounding refractive index. Experimental results reveal interesting differences with respect to the uncoated case, both in terms of spectral envelope and wavelength shifts related to cladding modes coupling.