Intracavity chemical absorption sensing using microresonator whispering-gallery modes
نویسندگان
چکیده
Chemical absorption is investigated using the evanescent fraction of a whispering-gallery mode (WGM). An effective absorption path length of about 50 cm is obtained in methane sensing and about 100 cm in a liquid dye solution.
منابع مشابه
Methods of Cavity-Enhanced Laser Absorption Spectroscopy Using Microresonator Whispering-Gallery Modes
Theoretical analysis of, and experimental results using, chemical sensing techniques based on microcavity-enhanced optical absorption are presented. Two methods are described in detail, and several extensions and enhancements of these methods are discussed briefly. Both techniques involve novel applications of tunable diode laser absorption spectroscopy in which cavity enhancement is provided b...
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