Mid-infrared supercontinuum (SC) generation in normally dispersive photonic crystal fiber (PCF) made of GeS₂-Ga₂S₃-CsI chalcohalide glass, is theoretically investigated. The finite difference method is employed to compute and optimize the different linear and nonlinear parameters of the fundamental guided mode. Simulation results indicate that the all-normal regime of dispersion over the entire wavelength range is achieved by properly reducing the diameter of the core neighboring air holes. The pulse propagation within the core of the proposed PCF and the SC generation process are accurately modelled and optimized, by numerically solving the generalized nonlinear Schrodinger equation. Both of Self Phase Modulation (SPM) and Optical Wave Breaking (OWB) effects are identified as the dominant nonlinear mechanisms involved in the pulse spectral broadening process. By launching at 3 μm, a 3 nJ energy and 50 fs duration input pulse into 15 mm long PCF, a broadband and highly coherent mid-infrared SC spectrum spanning the spectral region from 1.45 μm to 5.95 μm at 20 dB, is successfully generated.

用GeS ₂ -Ga ₂ S ₃制成的常色散光子晶体光纤（PCF）中产生中红外超连续谱（SC）从理论上研究了-CsI查卤玻璃。有限差分法用于计算和优化基本引导模式的不同线性和非线性参数。仿真结果表明，通过适当减小邻近气孔的纤芯直径，可以实现在整个波长范围内的色散正常状态。通过数值求解广义非线性薛定inger方程，可以精确地建模和优化拟议PCF核心内的脉冲传播和SC生成过程。自相位调制（SPM）和光波中断（OWB）效应都被认为是脉冲频谱展宽过程中涉及的主要非线性机制。通过以3μm发射，3 nJ能量和50 fs持续时间的输入脉冲到15 mm长的PCF中，