Design and analysis of a hexagonal tellurite photonic crystal fiber with broadband ultra-flattened dispersion in mid-IR

Abstract

We propose a modified hexagonal tellurite photonic crystal fiber (PCF) with broadband ultra-flattened dispersion near 2 μm regime. By optimizing various structural parameters, the dispersion of the proposed PCF can be kept within 60.47 ps nm−1 km−1 to 61.33 ps nm−1 km−1 from 2.15 μm to 2.85 μm wavelength. More importantly, the corresponding nonlinear coefficients can be as high as 378.1 W−1 km−1. Leveraging on these advantages, this fiber is suitable for supercontinuum generation toward mid-infrared (MIR) wavelength range. By injecting the hyperbolic secant pulse with peak power of 5 kW and full width at half maximum (FWHM) of 176 fs into the fiber, supercontinuum spectrum covering 2000–4900 nm together with the dispersive wave locating near 933 nm can be produced.