BUFFER GASES TO INCREASE THE EFFICIENCY OF AN OPTICALLY PUMPED FAR INFRARED D-2O LASER
The effects of buffer gas additives on the performance of an optically pumped D-2O laser operating at 385 mum have been investigated both experimentally and by numerical simulation. Three gases, sulphur hexafluoride, carbon tetrafluoride, and eta-hexane, were found to produce an increase of up to 40 percent in the pumping efficiency, as well as significant lengthening of the far infrared pulse. Under optimum conditions, 2.6 J in a 1 mus long pulse have been obtained. The buffer gases are shown to eliminate the vibrational de-excitation bottleneck, which in pure D-2O leads to an accumulation of population in the upper vibrational level and, hence, a reduction in the efficiency of absorption of the pump beam. Comparison of the observed buffer gas effects with the predictions of a numerical simulation code based on a rate equation model gives information about the constants for vibrational and rotational relaxation rates due to D-2O D-2O and D-2O buffer gas collisions.
Bibliographic Reference: IEEE JOURNAL OF QUANTUM ELECTRONICS, VOL. QE-21 (1985), NO. 8, PP. 1278-1285
Record Number: 1989124129700 / Last updated on: 1987-01-01
Available languages: en