A comprehensive guide to intracavity absorption spectroscopy

Abstract

AbstractThe enormous sensitivity of intracavity absorption spectroscopy (ICAS), as well as its unique ability to tolerate high broadband losses caused by, e.g., optical windows and light scattering, is being exploited by only a few research groups worldwide. The reason seems to be the lack of comprehensive literature, such that the field remains difficult to access for non-experts, in particular for engineers and chemists, who might derive the most benefits from applying ICAS. In particular, the missing connection to this target audience appears to be two-fold: (i) the seeming complexity of the theory, and (ii) the necessity to setup homemade laser systems. However, once some basic understanding and knowledge is obtained, both aspects appear to be of similar complexity as with other spectroscopic techniques. Therefore, the current work is aiming at (i) providing a comprehensive review of the theoretical basics of ICAS, and (ii) describing the most important practical aspects that need to be considered for a successful realization of ICAS measurements. To ensure maximum clarity, illustrative practical examples of recent work are used throughout the paper.