Coherent Mid-IR Supercontinuum Generation using Tapered Chalcogenide Step-Index Fiber

Mid-IR supercontinuum generation has attracted lot of attention in recent years because many unique molecular absorption bands exist in this region, Additionally, mid-IR supercontinuum light sources are expected to have potential applications including bio-photonic diagnostics, nonlinear spectroscopy, and infrared imaging, For high-spatial-resolution imaging a spatially coherent supercontinuum light source is desirable. The optical fiber is the promising medium for the design and development of a highly spatially coherent mid-IR light source with the high brightness. Earlier, the broadband mid-IR supercontinuum generation has been reported using the optical fibers in different materials including tellurite, and chalcogenide, but, its coherence property has not demonstrated extensively. Recently, our group has demonstrated coherent mid-IR supercontinuum generation in step-index tellurite, tapered tellurite, and chalcogenide double clad fibers pumped with femtosecond laser.