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Seminar Announcement: Jean-Luc Adam

posted Apr 17, 2018, 5:37 AM by Stefano Varas   [ updated Apr 17, 2018, 5:38 AM ]

Announcement
Thursday, 24 May 2018, 15:00
Sala Grande Palazzina B via alla Cascata 56/C

"Chalcogenide glasses: optical properties and photonic devices"

Jean-Luc Adam
Institut des Sciences Chimiques de Rennes UMR CNRS 6226
Université de Rennes 1
jean-luc.adam@univ-rennes1.fr

Abstract
Vitreous materials based on chalcogen elements show large transparency that extends from the visible up to 15 µm in the infrared. This is due to the lower phonon energies of chalcogenides, which are also responsible for enhanced luminescence of rare-earth (RE) ions in these matrices. In addition, chalcogenide glasses contain large polarizable atoms and external lone electron pairs which induce exceptional non-linear properties as compared to oxide glasses.
As far as shaping is concerned, specific chalcogenide glass compositions can be obtained in the form of optical lenses by molding; they can be also drawn in optical fibers or deposited as thin films and planar waveguides.
Applications are directly related to these unique optical properties and shaping abilities. For example, chalcogenide lenses are implemented in cameras for infrared imaging, and fibers are well adapted for optical sensing of biomolecules. Chalcogenide glasses doped with RE ions possess a high potential for applications as infrared sources. Besides, small-core photonic crystal fibers are capable to enhance non-linear optical properties for the generation of supercontinuum in the infrared.

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Stefano Varas,
Apr 17, 2018, 5:37 AM