Optical parametric amplification in capillary-assisted chalcogenide optical fibers

Micro- or nano- sized air capillary assisted optical fibers have attracted great interest due to variety of device oriented applications [1-3]. The presence of air-capillary into the core region of an optical fiber provides a platform to fill it with different type of liquids [4], adding tunability functionality to the device. In this work, we have theoretically investigated a capillary-assisted chalcogenide optical fiber (CCOF), where a capillary is introduced into As₂S₃ core optical fiber. We have numerically obtained the parametric amplification characteristics of such optical fiber systems and studied the tunability behavior. Chaudhari et. al. [5] has reported parametric gain in chalcogenide core and tellurite clad fibers. As₂S₃ is a promising nonlinear material for compact fiber optic devices due to its wide transparency window, up to ~1 μm, and large value of nonlinear refractive index, 2×10¹⁸m²/W in the longer wavelength infrared (IR) regime.