Micro/nano-structured optical fiber laser spectroscopy

Abstract

Micro/nano-structured optical fiber laser spectroscopy refers to laser spectroscopy with hollow-core or micro/nano-scale solid-core optical fibers as the sample cells. Light-matter interaction takes place inside or in the close vicinity of the core. This paper reviews the basics of light propagation in micro/nano-structured optical fibers, introduces the theory and construction of gas/liquid cells with these fibers, and reports the recent progress of gas/liquid detection with direct absorption, photothermal, photoacoustic, fluorescence and Raman spectroscopy as well as possible further research directions. A micro/nano-structured optical fiber tightly confines a light mode in or near the fiber core and has a large fraction of mode field in air, which enables strong light-matter interaction over a long distance. The use of micro/nano-structured optical fiber as the sample cells would improve the performance of existing spectroscopic techniques as well as create novel spectroscopic methods. The optical fiber sample cells may be flexibly connected to other photonic components, promoting miniaturization and practical applications of spectroscopic sensing and instrumentation. 微纳结构光纤光谱学是指以空芯微结构或微纳光纤为样品池，光和物质在纤芯内部或表面进行相互作用的光谱学技术。本文回顾空芯和微纳光纤导光的基本原理，介绍气体、液体样品池构建的理论和方法，综述基于光谱吸收、光热、光声、荧光、拉曼等效应的微纳结构光纤光谱学的最新进展及今后可能的发展方向。微纳结构光纤对光场的束缚能力强、模场能量在空气中的比例高，可实现光和物质在其中的高效、长距离相互作用。微纳结构光纤样品池的采用，可提升传统光谱学系统的性能或构建新型的光谱学系统；应用传输光纤与其他光学元器件进行柔性连接，可促进光谱学仪器和传感器的小型化和实用化。