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We report on the generation of multiple-octave supercontinuum laser source spanning from 0.5 μm to 11 μm induced by multi-filamentation in a ZnSe crystal. The generated supercontinuum is both spatially and spectrally characterized. It is then exploited in a proof-of-principle experiment for methane spectroscopy measurements by means of the supercontinuum absorption spectroscopy technique. The entire absorption spectrum is successfully recorded within the whole spectral bandwidth of the supercontinuum. Experimental results are in fairly good agreement with the HITRAN database, confirming the reliability and stability over several hours of the generated supercontinuum.

Microstructured optical fibers (MOF) can be seen as next generation fiber of significance in advancing the compact optics because of its excellent compatibility in integrated optics. However, the degradation of their physicochemical properties limits their efficiency and lifetime. Atmospheric moisture is responsible for the degradation of amorphous systems especially chalcogenide glasses. In the light of previously reported studies, in order to clarify the aging process continuously evolving in sulfide microstructured optical fiber over time, a detailed investigation of this phenomenon has been conducted. The time-dependent transmission and glass chemical deterioration have been studied for As 2 S 3 MOF with regard to their exposure to different atmospheric conditions. Results show a substantial impact of atmospheric moisture through an interaction with the glass network. Significant improvement has been registered by storing the fibers under dry atmosphere.

We report the fabrication and the characterization of low OH content and low loss tellurite optical fibers. The influence of different methods of glass fabrication on fiber losses has been investigated. The use of the purest commercial raw materials can reduce the losses below 0.1 dB/m at 1.55 μm. Incorporation of fluoride ions into the tellurite glass matrix makes the optical fibers transparent up to 4 μm. A suspended core microstructured fiber has been fabricated and pumped by nanojoule-level femtosecond pulses, thus resulting in more than 2000-nm bandwidth supercontinuum after a few centimeters of propagation.

The vitreous formation in a new chalcohalogenide system based on As, Sb, Bi, S, Pb and I has been studied. Wide vitreous regions have been identified both in the ternary As 2 S 3 –Sb 2 S 3 –PbI 2 system and in the quaternary As 2 S 3 –Sb 2 S 3 –Bi 2 S 3 –PbI 2 system. More particularly, in the latter case, the vitreous regions have been investigated and established for the two layers of the system corresponding respectively to 10% and 20% molar of Bi 2 S 3 . Due to the richness of these new glasses in highly polarizable elements, they are of interest for the implementation of high nonlinear optical properties. To explore the potentialities of chalcogenide glasses for ultra-fast optical applications, the nonlinear refractive indices (real and imaginary part) of different compositions are measured. Nonlinear measurements have been performed through a pump/probe experiment using a Mach-Zehnder interferometer coupled to a CCD camera. The measured values are as high as 16×10 −18 m 2 /W for the nonlinear refractive index and 6 cm/GW for the nonlinear absorption.

Fluoride glasses involved in the realization of laser sources are described. Observed lasing wavelengths, which range from the blue to the mid infrared in fluoride glass optical fibers are reviewed. Also, recent results on planar waveguides, including fabrication and optical properties, are presented.