高非线性光子晶体光纤深紫外超连续谱的研究  

Deep Ultraviolet Supercontinuum Study in the Highly Nonlinear Photonic Crystal Fiber

作　　者：杨建菊[1,2] 韩颖[1,2] 王伟[1,2] 周桂耀[1,2] 赵兴涛[1,2] 侯蓝田[1,2] 屈玉玮[1,2] 牛静霞 

机构地区：[1]燕山大学信息科学与工程学院,河北秦皇岛066004 [2]燕山大学河北省特种光纤与光纤传感重点实验室,河北秦皇岛066004

出　　处：《光谱学与光谱分析》2017年第4期1215-1219,共5页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(61205084;61405173;61405172;61307110);河北省自然科学基金项目(F2014203194)资助

摘　　要：光子晶体光纤作为光学非线性良好介质,对超连续谱产生具有重要作用。深紫外超连续谱光源在许多应用中有急切的需求,然而由于实验条件和光纤参数等方面的影响,利用高非线性光子晶体光纤产生深紫外(<280nm)超连续谱的报道较少。通过理论和实验研究了高非线性光子晶体光纤在深紫外区的频率变换,并分析其产生的物理机理。使用钛宝石飞秒激光器将实验室自制的光子晶体光纤在反常色散区泵浦,研究了不同泵浦功率和泵浦波长对深紫外区超连续谱的影响,结果表明:泵浦波长固定为860nm时,深紫外频率光谱展宽范围随泵浦功率的增加而逐渐展宽;泵浦功率固定为0.4 W时,泵浦波长的增加不仅展宽超连续谱范围而且极大的提高了深紫外区光谱的转换效率。当泵浦波长为870nm,泵浦功率为0.4 W,实验所用光子晶体光纤长度为1.45m,零色散波长为825nm时,光子与色散波的交叉相位调制使深紫外基模超连续谱扩展到最短波长212nm。Photonic crystal fiber is a good nonlinear medium which plays an important role in generating supercontinuum. Deep ultraviolet supercontinuum light sources in many applications have urgent needs, hut due to the influence of experimental conditions and fiber parameters, using highly nonlinear photonic crystal fiber produced deep ultraviolet supercontinuum （~280 nm） has reported less. In this paper, we study the frequency conversion of high nonlinear photonic crystal fiber in the deep ultra- violet region, and analyze its physical mechanism through theoretical and experimental. Photonic crystal fiber with length of 1.45 m and the zero dispersion wavelength of 825 nm made in our lab is pumped by the femtosecond Ti： sapphire laser in the abnormal region and the dependences o{ deep ultraviolet supereontinuum on the different pump powers and pump wavelengths are investi- gated. The experiment results show that when the pump wavelength is fixed to 860 nm, the broadening range of deep ultraviolet supercontinuum is gradually broadened with the increase of pump power; when the pump power is fixed to 0.4 W, the cross- phase modulation between the solitons and the dispersive waves can effectively extend the fundamental mode deep ultraviolet su- pereontinuum into the wavelength of 212 nm. The increase of pump wavelength not only broadens supereontinuum range but also greatly improves the conversion efficiency of deep ultraviolet supercontinuum.

关 键 词：深紫外 光子晶体光纤 反常色散区 超连续谱 

分 类 号：TN252[电子电信—物理电子学]