Abstract

Concentration modulation is demonstrated to be a technique capable of markedly extending sensitivity limits in absorption spectroscopy. The gain generated relates in such a manner to sample transmittance that for the first reported time direct spectroscopic concentration measurements become possible. When concentration modulation is used with picosecond lasers, state lifetimes can be determined to a limit of ~20 psec.

© 1985 Optical Society of America

Rate-equation model for quantitative concentration measurements in flames with picosecond pump–probe absorption spectroscopy

Gregory J. Fiechtner, Galen B. King, and Normand M. Laurendeau
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Laser spectroscopy using beam-overlap modulation

T. P. Duffey, D. Kammen, A. L. Schawlow, S. Svanberg, H.-R. Xia, G.-G. Xiao, and G.-Y. Yan
Opt. Lett. 10(12) 597-599 (1985)

Infrared absorption spectroscopy of single particles using photophoresis

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J. Opt. Soc. Am. B 2(9) 1510-1526 (1985)