Abstract
Two different architectures of multiplexers/demultiplexers based on 4 x 1 and 1 x 4 configurations are discussed. These architectures are implemented using apodized fibre Bragg gratings as optical filters and optical circulators. The spectral characteristics of the devices for channel separations of 100 GHz and 50 GHz are analysed and their performance is evaluated. Optical switch and cross-connect configurations are also demonstrated.

Abstract
In this paper we present and evaluate the spectral response of uniform gratings written in different tapered core sections of single mode fibre. This combination of uniform gratings and tapers leads to three, types of Chirped Fibre Bragg Gratings with different reflection spectra and different mechanical properties. These devices are characterized in function of the applied strain, showing interesting chirp tunability.

Abstract
A multiplexer/demultiplexer for 100 GHz channel spacing based on chirped fibre Bragg gratings with different bandwidths and optical circulators is presented. The spectral characteristics, specifications and operation of these passive devices are described, showing its potential use in DWDM applications.

Abstract
We present and demonstrate a 20 nm tunable L-band fiber ring laser. Tunability is achieved by curving a simple taper which controls the intra-cavity loss.

Abstract
We have flattened the gain spectrum of a commercial Erbium-doped fibre amplifier, obtaining a curve with approximately 3 dB of ripple, from 1524 nm to 1551 nm, using long-period fibre gratings as equalising optical filters. The fabrication principle of the long-period fibre grating is based on the electric arc technique.

Abstract