飞秒激光蚀刻光纤微腔及其在光纤环衰荡腔中的应用  

Micro-Cavity Fabricated by Femtosecond Lasers and Its Application in Fiber-Loop Ring-Down Spectroscopy

作　　者：张绮[1] 张伟刚[1] 张健[1] 刘卓琳[1] 姜萌[1] 刘亚萍[1] 林锦海[1] 

机构地区：[1]南开大学现代光学研究所,光电信息技术教育部重点实验室,天津300071

出　　处：《中国激光》2009年第3期713-717,共5页Chinese Journal of Lasers

基　　金：国家自然科学基金(10674075,60577018)资助课题

摘　　要：为了实现在光纤环衰荡腔(FLRD)系统中的微量气体液体传感,提出了利用飞秒激光微纳加工的方法加工微流体传感装置。利用800 nm的飞秒激光脉冲在普通980 nm,1550 nm的单模光纤上实现了直写光学微腔,微腔的宽度达到4μm,深度80μm。将在单模光纤刻蚀的光学微腔成功应用于光纤环衰荡腔系统之中。针对光纤环衰荡腔的系统装置,分析了该系统的探测原理,并对该系统应用于微流体吸收探测中所探测的衰荡时间、损耗及待测流体浓度的关系进行理论推导。利用此系统,实现了对微量流体浓度的吸收谱高灵敏度探测。In order to realize the sensing probe of micro-scale liquid and gas in fiber cavity ring-down spectroscopy system, a new method of fabricating microfluidic sensing devices is proposed. The micro-cavity on single mode 980 nm and 1550 nm fibers by direct writing is achieved with a focused near-IR 800 nm femtosecond laser beam. The width of the cavity is 4 μm, with the depth of 80 μm. The micro cavity directly written by femtosecond laser is successfully applied into fiber-loop ring-down (FLRD) spectroscopy, and its detection principle is analyzed. It is used in micro-cavity liquid absorb detection, and the relation between the detected ring-down time, the loss and the liquid concentration is deduced. With this micro-cavity, FLRD spectroscopy can realize gas and fluidic absorption measurement on micro-scale.

关 键 词：传感器 光学微腔 飞秒激光 光纤环衰荡腔光谱 

分 类 号：TN247[电子电信—物理电子学] TP212.14[自动化与计算机技术—检测技术与自动化装置]