Glass-based Confined Structures and Nanocomposite Materials for Photonics

During the last years, the spreading of optical networks toward the final customers has triggered the research in innovative materials and processes for development of compact and integrated optical devices. The possibility to develop optical confined structures and fabricate nanostructured multi-component materials has opened new possibilities both in the field of basic and applied physics in a large area covering Information Communication Technonologies, Health and Biology, Structural Engineering, and Environment Monitoring Systems. The aim of this lecture is to highlight and discuss some advances in glass-based photonic systems, mainly rare-earth-activated, where suitable geometries and appropriate innovative materials allow tailoring and enhancement of optical and spectroscopic properties. In particular, the following topics are presented: (i) planar optical waveguides, that, together with optical fibers, represent the most popular guided-wave structure; (ii) dielectric 1-D photonic band gap structures or planar microcavities, where the rare-earth luminescence is enhanced and selected in frequency; (iii) dielectric 3-D photonics crystals which can lead to photonic devices such as switches, mirrors, filters and superprisms; (iv) dielectric spherical microresonators, where the light can be guided through whispering-gallery modes; (v) rare earth-activated glass ceramics, where the active ions are embedded in the crystalline phase, combining the mechanical and optical properties of the glass with a crystal-like environment for the rare-earth ions; (vi) Nanostructured multicomponent systems that can be employed as broadband sensitizer for Er3+ luminescence.