Original designs of chalcogenide microstructured optical fibers for mid-IR applications

Compared to oxide based glasses, vitreous materials composed of chalcogen elements (S, Se, Te) show large transparency windows in the infrared. Indeed, chalcogenide glasses can be transparent from the visible up to 12 - 18 μm, depending on their compositions. In addition, chalcogenide glasses contain large polarisable atoms and external lone electron pairs which induce exceptional non-linear properties. Consequently, the non-linear properties can be 100 or 1000 times as high as the non-linearity of silica. An original way to obtain single-mode fibers is to design microstructured optical fibers (MOFs). These fibers present unique optical properties thanks to the high degree of freedom in the design of their geometrical structure. Our group has prepared various chalcogenide MOFs operating in the IR range in order to associate the high non-linear properties of these glasses and the original MOF properties. Indeed, chalcogenide MOFs might lead to new devices with unique optical properties in the mid-infrared domain like multimode or endlessly single-mode transmission of light, small or large mode area fibers, highly birefringent fibers and non-linear properties for wavelength conversion or generation of supercontinuum sources.