Novel device structures for fiber gratings

Summary form only given. An area of recent excitement is the study and application of silica fiber waveguide devices with enhanced properties. These device structures fall into two general categories: 1) highly integrated tunability; and 2) radical modification of the index profile from that in a conventional fiber. The paper describes a range of novel waveguide structures that enhance the functionality of fiber gratings and show great potential for further applications. They include per-channel dispersion trimming devices and electrically tunable broadband fiber filters that use integrated thin-film metal heaters as well as novel grating filters that exploit the unique properties of air-silica and hybrid air-silica-polymer microstructured fibers