Seminar Announcement: Trevor Benson

Data pubblicazione: 5-mar-2019 18.40.11


Tuesday, 26 February 2019, 10:30

Sala Grande Palazzina B via alla Cascata 56/C

"Assessing the optical properties of chalcogenide glasses at mid-infrared (MIR) wavelengths"

Trevor Benson

George Green Institute for Electromagnetics Research, Faculty of Engineering,

University of Nottingham, University Park, Nottingham, NG7 2RD,

United Kingdom



Abstract Refractive index dispersion is one of the critical parameters that influences the design of optical components. Prism measurements in our laboratory can determine the mid-infrared refractive index of chalcogenide glasses to a standard deviation of precision of less than 0.002. However, shortcomings of this technique are that it requires multiple light sources and intensive sample preparation. The modelling of transmission spectroscopic data [1] is an attractive alternative and was extended by us into the mid-infrared (MIR) region by introducing a two- term Sellmeier equation [2]. This approach determines the refractive index dispersion of chalcogenide glasses to an accuracy of better than 0.4 %. The presentation we will review this method, and discuss its recent extensions to determining very small refractive index contrast and the evaluation of thermo-optic coefficients.