Abstract
The sol-gel method was employed to obtain poly(oxyethylene) (POE)/siloxane hybrids (di-ureasils) doped with erbium triflate (Er(CF3SO3)(3)). The host hybrid matrix employed is composed of a siliceous framework to which short POE chains are covalently bonded through urea linkages (-NH(C(=O)NH-). Xerogels with infinity > n >= 5 (where n, salt composition, is the molar ratio of OCH2CH2 moieties per Er3+ ion) were analyzed. Samples with n >= 20 are amorphous. Those with n > 20 are thermally stable up to about 325 degrees C. In the di-ureasils proposed, the Er3+ ions are active at room temperature (RT). Concentration effects on the quenching of the 1.53 mm emission intensity (excited at 488 nm) are negligible.

Abstract
This article presents results of device fabrication using UV processing of materials and integrated optic components produced by flame hydrolysis deposition and hybrid sol-gel technology. Photosensitive materials were employed in the fabrication of channel waveguides and channel photo-imprinted waveguides incorporating Bragg gratings through single and double-step exposure.

Abstract
A single long-period fibre grating was written in a biconical fibre taper made from standard communications step-index optical fibre, resulting in an interferometric fibre sensor device that provided a resolution of 1 × 10-4 for refractive indices in the range of 1.30 to 1.34, suggesting that these devices may be suitable for use with aqueous solutions. © IEE 2005.

Abstract
Fabrication of organic-inorganic sol-gel glass channel waveguides by ultraviolet (UV) photopolymerization of material synthesized from the precursor methacryloxypropyltrimethoxysilane is performed using a pulsed 248-nm excimer laser without the need of photoinitiators. The transmission spectra of channel waveguides are presented. Absorption bands are identified, revealing high loss (4-5 dB/cm) at 1.55 mum mainly due to strong OH group content and an acceptable value of 0.4 dB/cm at 1.3 mum. Heat treatment and UV irradiation showed similar effects on the transmission spectra of channel waveguides, revealing no loss improvement in the 1.55-mum region.

Abstract

Abstract
Organic-inorganic hybrids were prepared using ureapropyltriethoxysilane, methacryloxypropyltrimethoxysilane and acrylic acid modified zirconium(IV) n-propoxide precursors and were characterized by small angle X-ray scattering, X-ray diffraction and photoluminescence spectroscopy. The results indicate an effective interaction between the zirconium-based nanoparticles and the siliceous nanodomains that induces changes in the hybrids' emission features. Planar waveguides were obtained by spin-coating of the prepared sols on sodalime and silica substrates. Refractive index, thickness, number of propagating modes, and attenuation coefficient were measured at 543.5, 632.8 and 1550 nm by the prism coupling technique. The synergism between the two hybrid precursors resulted in monomode planar waveguides with low losses in the infrared ( from 0.6-1.1 dB cm(-1)) which also support a number of propagating modes in the visible ( losses from 0.4-1.5 dB cm(-1)). Channel waveguides were also obtained by UV photopatterning using amplitude or phase masks and propagating modes were observed at 1550 nm.