光电工程, 2016, 43 (3): 23, 网络出版: 2016-09-12
双零色散点锥型微结构光纤的超连续谱
摘要
用“快速低温”法,在保持包层空气填充率不变的情况下,对实验室自制的微结构光纤进行了拉锥,得到了锥长分别为 8 mm、10 mm的锥形光纤。利用多极法模拟可知,拉锥前光纤在 1 129 nm具有单个零色散点,拉锥后光纤锥腰处出现双零色散点,对于 8 mm、10 mm锥长,其零色散点分别为 806 nm /2 456 nm和 637 nm /1 164 nm。8 mm锥微结构光纤在中心波长 800 nm、平均功率 0.45 W的超短脉冲作用下,产生了 378 nm~1 632 nm、 1777 nm~2 450 nm平坦度为 20 dB的超连续谱;当功率为 0.50 W时,10 mm锥微结构光纤位于 1 164 nm的零色散点限制了拉曼孤子及超连续谱的红移,但在 395 nm~475 nm形成谱宽为 80 nm峰,频率上转换效率达到 70.5%。
Abstract
By “fast and cold tapered technology”, a home-made Microstructure Fiber (MF) is tapered to 8 mm, 10 mm
tapered length while keeping d/Λ unchanged. Numerical simulations by multi-pole method show that untapered MF has a
single Zero Dispersion Wavelength (ZDW) at 1 129 nm, while after tapering an additional ZDW appears at tapered waist.
The two ZDWs of 8 mm and 10 mm-tapered-MF locate at 806 nm/2 456 nm and 637 nm/1 164 nm, respectively. When
pumped by ultrafast pulse with center wavelength at 800 nm and average energy of 0.45 W, 8 mm-tapered-MF generates
supercontinuum at range of 378 nm~1 632 nm and 1 777 nm~2 450 nm with 20 dB flatness. In 10 mm-tapered-MF, redshift of Raman soliton and supercontinuum is hindered by its second ZDW at 1 164 nm. However, the blue shift efficiency
of bump energy is enhanced. When pump power reaches 0.5 W, up to 70.5% of pump energy is unconverted to 395 nm~
475 nm.
韩颖, 刘志宏, 毕新英, 周桂耀, 屈玉玮, 齐跃峰, 王伟. 双零色散点锥型微结构光纤的超连续谱[J]. 光电工程, 2016, 43(3): 23. HAN Ying, LIU Zhihong, BI Xinying, ZHOU Guiyao, QU Yuwei, QI Yuefeng, WANG Wei. [J]. Opto-Electronic Engineering, 2016, 43(3): 23.