Jean-Luc ADAM

Abstract:

Vitreous materials based on fluorides or on chalcogen elements (S, Se, Te) show large transparency windows in the infrared. Indeed, fluoride glasses are transparent from the UV to 7 micrometers in the infrared, while chalcogenides can be transparent from the visible up to 12-15 micrometers, depending on their compositions [1]. This is due to the lower phonon energies of non-oxide glasses, which are also responsible for enhanced luminescence of rare-earth ions embedded in such matrices, as compared to oxides. Thus, these glasses allow light emission at wavelengths not accessible with silica. In addition, chalcogenide glasses contain large polarisable atoms and external lone electron pairs that induce exceptional non-linear properties. The non-linear properties of chalcogenides can be 100 to 1000 times as high as the non-linearity of silica.
As far as shaping is concerned, specific fluoride and chalcogenide glasses can be obtained in the form of optical fibers. Applications are directly related to the combination of unique optical properties and shaping abilities.
The presentation deals with an overview of the synthesis and properties of non-oxide glasses, completed by the latest results, in terms of applications, in two fields of technological or societal importance. The first one is the generation of supercontinuum of infrared light by using fluoride and/or chalcogenide optical fibers [2-4]. The second one is the detection of green-house-effect gases like CO₂ by using optical sensors based on rare-earth-doped chalcogenide fibers [5].

[1] J. Sanghera and D. Gibson, Optical Properties of Chalcogenide Glasses and Fibers, in Chalcogenide Glasses, eds., J.L. Adam and X.H. Zhang (Woodhead Publishing, Cambridge, UK), pp. 113-138 (2014).
[2] R.A. Martinez, G. Plant, K. Guo, B. Janiszewsji, M.J. Freeman, D.L. Maynard, M.N. Islam, et al., Opt. Lett. 43 (2018) 296-299
[3] U. Moller, Y. Yu, I. Kubat, C. R. Petersen, X. Gai, L. Brilland, D. Mechin, C. Caillaud, J. Troles, B. Luther-Davies, and O. Bang, Optics Exp. 23 (2015) 3282-3291
[4] C. Caillaud, C. Gilles, L. Provino, L. Brilland, T. Jouan, S. Ferre, M. Carras, M. Brun, D. Mechin, J.-L. Adam, and J. Troles, Optics Exp. 24 (2016) 7977-7986
[5] A.L. Pele, A. Braud, J.L. Doualan, R. Chahal, V. Nazabal, C. Boussard-Pledel, B. Bureau, R. Moncorge, and P. Camy, Optics Express 23 (2015) 4163