Tin dioxide based photonic systems

Summary form only given. In this work, due to the challenge for improving the efficiency of photonic materials actived by Rare Earth ions (RE), Tin dioxide (SnO2) nanocrystals based glass ceramic was employed and it was proved as a viable photonic material. The base material for doping RE ions was formed by embedding Tin dioxide nanocrystals into silica. The properties of the material were investigated by both simulations and experimental characterisation. The material was fabricated by sol-gel routes in different geometrical systems : thin films, monoliths and planar waveguides. The characterisation of the thin films showed the fundamental properties of the material : structural, morphological and optical properties. The presence of Tin dioxide nanocrystals led to the increase of both solubility and emission of RE ions. The energy transfer from the nanocrystals to the RE ions was proved by experiments and the result was again clarified by the simulations on the structure and the bandstructure of Er3+ ions substituting for Sn4+ ions in the nanocrystals. The results confirmed the advantages of Tin dioxide as luminescence sensitizer [1] for Er3+. Following the approaches of Tin dioxide based thin films, monoliths and planar waveguides have been fabricated for further processing into photonic devices : fibers, solid lasers and integrated circuits. In order to obtain the crack-free and densified monoliths, the synthesis and heat-treatment process of the xerogels have been optimized. Thermal analyses were performed in order to identify the heat-treatment stategy. Up to now, heat-treatment at 950°C for 100h has shown the best performance on H2O removal, densification of the monoliths and crystallization of SnO2 nanocrystals. By characterisation of the exictation and emission of the monoliths, the indirect excitation due to energy transferring from SnO2 into Er3+ has been shown to be more efficient than the other direct excitations. The monoliths excited at 335nm, which corresponds to the bandgap of SnO2 nanocrystals, showed the highest emission intensity at 1534nm (Figure 1). The Tin dioxide based waveguides have shown the good transparency with transmittance higher than 90% in UV-Vis-NIR regions and waveguiding properties (Figure 2) with low losses