Abstract
An all-optical scheme for simultaneous determination of oxygen and temperature is presented. A ruthenium complex immobilized in a non-hydrolytic sol-gel matrix is used as oxygen sensor. Temperature information is provided by CdSe quantum dots immobilized in the same material. While the dye luminescence is quenched by oxygen and temperature, the nanocrystals luminescence depends only on temperature. Results presented demonstrate that the combined luminescence response allows to simultaneously assess both parameters using a single optical fiber system.

Abstract
In this work it is presented a novel in-fibre modal interferometer based on a non-adiabatic biconical fused taper that couples light between the cladding and the core, combined with the Fresnel reflection at the fibre end. It is observed that the returned liaht from this fibre structure shows a channelled spectrum similar to that of a two-wave Michelson interferometer. The application of this device as a fibre optic flowmeter sensor is demonstrated.

Abstract

Abstract
We study the origin of antisymmetric perturbation of the fiber in are-induced long-period gratings that couple the core mode into the antisymmetric cladding modes. We demonstrate that this perturbation is caused by a temperature gradient in the fiber, which is induced, in turn, by a temperature gradient in the arc discharge.

Abstract
Differential group delay (DGD) generation by inducing birefringence in uniform fiber Bragg gratings (FBG) is studied. Applying a transverse load, a birefringence is induced on a uniform FBG creating a tunable differential group delay. A theoretical behavior of this phenomenon is presented being in good agreement with the experimental results obtained. A maximum experimental tunable DGD of similar to 60 ps was obtained with this induced birefringent process in the uniform FBG. (C) 2007 Wiley Periodicals. Inc.

Abstract
A linear tunable dispersion compensation device based on a chirped grating (CFBG) mounted on a stretching mechanical structure is described. The tunability is obtained changing the CFBG bandwidth without modification of the total length structure. (c) 2007 Wiley Periodicals, Inc.