提出了一种基于高非线性氟化镁光子晶体光纤产生紫外超连续光源的方法。采用分步傅里叶法求解光纤的非线性薛定谔方程,基于光子晶体光纤数值模拟了扩展到紫外波段的超连续谱的产生;通过分析光纤结构参量与泵浦光源参数对紫外超连续谱产生的影响,得出了光纤长度、色散参量以及泵浦脉冲峰值功率、初始脉冲宽度对超连续谱光谱宽度的影响规律。研究发现:当光子晶体光纤长度为8 cm、脉冲中心波长为450 nm、峰值功率为3.1 kW、初始脉冲宽度为40 fs时,可获得展宽至紫外的超连续谱,范围为279.6~769.0 nm。

This paper proposes a method for generating an ultraviolet supercontinuum light source (SC) using highly nonlinear magnesium fluoride photonic crystal fiber (PCF). The nonlinear Schr?dinger equation was solved using the split-step Fourier method, and the generation of an ultraviolet SC in the PCF was numerically simulated. The effects of the structural parameters of the PCF and the parameters of the pump source on the ultraviolet SC were analyzed. The variations in the SC width relative to the PCF length, dispersion parameter, pump pulse peak power, and initial width of pump pulses were obtained. Simulation results reveal that the SC is extended into the ultraviolet range of 279.6--769.0 nm when the length of the PCF is 8 cm, central wavelength of the pump pulse is 450 nm, peak power is 3.1 kW, and initial pulse width is 40 fs.