Abstract
The near saturated behavior of diatomic molecules is modeled by considering the interactions of two sets of rotational levels. The molecules are assumed to be subjected to high intensity laser radiation tuned to one particular rotational transition between the sets of levels. Previous two-level models for atomic fluorescence are modified to account for the strong coupling of rotational energy levels in molecules. The steady-state rate equations for the system are manipulated to give a simple expression for the total fluorescence power in terms of the electronic quenching rate Q21, the spontaneous emission rate A21, the stimulated emission rate B21I21, and the population fractions of the lower and upper levels which are directly excited by the laser, F1(e) and F2(e), respectively. When the ratio of the rotational relaxation rates Q22 and Q11 to Q21 is on the order of 100 or less, the distribution of molecules among rotational levels is found to be markedly non-Boltzmann. The influence of the non-Boltzmann distribution on data interpretation is discussed.
© 1979 Optical Society of America
Full Article | PDF ArticleMore Like This
Robert P. Lucht, Donald W. Sweeney, and Normand M. Laurendeau
Appl. Opt. 19(19) 3295-3300 (1980)
Campbell D. Carter, J. Thaddeus Salmon, Galen B. King, and Normand M. Laurendeau
Appl. Opt. 26(21) 4551-4562 (1987)
M. B. Blackburn, J.-M. Mermet, G. D. Boutilier, and J. D. Winefordner
Appl. Opt. 18(11) 1804-1807 (1979)