ORC Seminar Series
"Rare-earth-doped nanoparticles in silica-based optical fibres"
Prof Bernard Dussardier
University of Nice-Sophia Antipolis, CNRS, Nice
Date: Wednesday 3 October 2007
Venue: Building 46/Lecture Theatre B (room 2003)
Rare-earth (RE)-doped optical fibre based devices have recently experienced tremendous progress. Silica-based fibres are cheap, reliable and able to sustain extremely high optical densities, compared to other alternative glasses. It is also expected that new active dopants in silica, as alternatives to the 'standard' Erbium, Ytterbium or Thulium ions, would offer access to optical amplification over broader or new spectral bands.
In order to broaden and/or flatten the dopants gain curve, it is necessary to control their spectroscopic properties. Standard silica glass modifiers such as aluminium give very good properties to available EDFA. However, for more drastic spectroscopic changes, more important modifications of the rare-earth ions local environment are required. Also silica often provides low quantum efficiency to some interesting RE optical transitions, mostly due to high local phonon energy or local site symmetry.
Hence, we explore the potential of encapsulating RE ions in glass nanoparticles (NP) within the fibre glass, in order to provide them with specific local compositional and/or structural environment. We will particularly show recent results on amorphous nanoparticles doped with Erbium ions, embedded in silica preforms and fibres.
Bernard Dussardier received his PhD in 1992 in Nice (France), and worked at the ORC as a post-doc from 1992-1995. Since 1995 he has been research scientist at CNRS at the "Laboratoire de Physique de la Matiere Condensee", University of Nice-Sophia Antipolis, where he is leading the Active Optical Fibre Group. He received his 'HDR' (equiv. to A/Professor) in July 2007.
His main research interests are in designing, preparing, and studying speciality optical fibres, doped with transition metal and/or rare-earth ions, or fibres with special waveguiding properties (chromatic dispersion, non-linearities). He also has interests in demonstrating new devices based on the fibres he is developing, such as amplifiers, sensors and lasers.
Copyright University of Southampton 2006