ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
The removal rates of the lower levels of the XeF(B→X) excimer laser transitions strongly affect the overall efficiency of the E-beam-pumped devices. We have deduced the removal rates of XeF(X,v) in argon, helium, and neon by measuring the populations of vibrational levels v=0, 1, 3, and 4 formed by the photolysis of XeF2. The time history of each vibrational population is monitored with a cw tunable dye laser tuned to an absorption feature of the selected vibrational/rotational level. The studies show a rapid vibrational relaxation followed by a common decay rate of the coupled vibrational levels. Helium and neon were found to remove these levels with the same rate coefficient of (2.0±0.2)×104 (s Torr)−1 at room temperature. The corresponding rate coefficients for argon were larger by about 25%. The removal rate coefficients increased with temperature in the range of T=23–95 °C. The rate coefficient for the vibrational excitation of v=0 by helium was measured to be (3.6±0.7)×105 (s Torr)−1 at room temperature. This is considerably larger than the value of (4.8±1.5)×104 (s Torr)−1 previously reported by Fulghum et al. Fast vibrational relaxation is required to empty the lower levels of the laser transitions so that vibrational "bottlenecking'' does not terminate the laser prematurely.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.454850
