Dispersion Engineered Capillary-Assisted Chalcogenide Optical Fiber Based Mid-IR Parametric Sources

We report the detailed theoretical investigations of a capillary-assisted chalcogenide optical fibers exhibiting three zero dispersion wavelengths and small magnitude of chromatic dispersion. The dispersion characteristics of the proposed fiber can be tailored externally by temperature when the air-capillary is infiltrated with suitable thermooptic liquids. This has led to design and development of thermally tunable broadband CW pumped optical parametric amplifier (OPA) in mid-IR region with bandwidth greater than 2000 nm. By considering the sixth-order dispersion parameter in the phase-matching condition, we have shown the temperature-dependent various phase-matching topologies which are only possible with different fiber structures as reported earlier. The key benefits of the proposed tunable OPA are the generation of new radiations of varying line widths.