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Experimental Apparatus and Technique for Optical Coherent Spectroscopy of Gases

Igor V. Yevseyev, Valery M. Yermachenko, Самарцев Виталий Владимирович

Published Feb 24, 2004• 0 citations

Abstract

This chapter is devoted to the description of the main methods employed in the investigation of optical transient processes in gas media and the apparatus used in these studies. Recently, a new direction of laser spectroscopy has appeared. This direction is based on several methods of extracting the information concerning a resonant medium, including: a ) analysis of decay curves for the intensities of optical coherent responses within certain time intervals; b) analysis of temperature lowering, i.e., the dependencies of the intensities of coherent responses on the temperature of a gas medium under study; c) investigation of the modulated structures of optical coherent responses related to the hyperfine coupling of unpaired electrons with nuclei of molecules or atoms in the gas (modulation coherent spectroscopy), including the regime of double resonances; d) polarization coherent spectroscopy associated with the identification of the type of the energy transition being studied and the determination of characteristics of this transition from the polarization properties of optical coherent responses; e) the method of optical “coherent averaging,” which is closely related to a multipulse excitation of gas particles and the regime of double resonances; and ƒ) the method of angular spectroscopy, which is based on the spatial features of the generation of optical coherent responses and superradiance.

DOI: 10.1201/9780203642696-3

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