Plasma chemistry of the sealed-off slab CO laser active medium pumped by radio-frequency discharge with liquid-nitrogen-cooled electrodes

Journal Article · Fri Sep 15 04:00:00 EDT 2017 · Plasma Physics Reports

DOI:https://doi.org/10.1134/S1063780X17090033· OSTI ID:22760306

Kozlov, A. Yu.; Seleznev, L. V.

The long-term time behavior of the output power of a sealed-off cryogenic slab CO laser pumped by a repetitively pulsed RF discharge and operating on the overtone (λ = 2.6–3.5 μm) vibrational−rotational transitions of the CO molecule was studied experimentally. It is shown that adding of an anomalously large amount of oxygen (up to 50% with respect to the CO concentration) to the initial gas mixture CO : He = 1 : 10 leads to a manyfold (by several tens of times) increase in the duration of the laser operating cycle (until lasing failure due to the degradation of the active medium). In this case, the laser life-time without replacement of the active medium reaches 10{sup 5}–10{sup 6} pulses. Using various diagnostics (including luminescence spectroscopy and IR and UV absorption spectroscopy), regularities in the time-behavior of the concentrations of the main component of the active medium (CO molecules) and the products of plasmachemical reactions (O{sub 3}, CO{sub 2}) generated in the discharge gap during the laser operating cycle are revealed. Time correlation between the characteristics of the active medium and the laser output power are analyzed. A phenomenological approach to describing the entirety of plasmachemical, purely chemical, gas-dynamic, and diffusion processes determining the behavior of the laser output characteristics throughout the laser operating cycle is offered.

• OSTI ID: 22760306
• Journal Information: Plasma Physics Reports, Journal Name: Plasma Physics Reports Journal Issue: 9 Vol. 43; ISSN PPHREM; ISSN 1063-780X
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ABSORPTION SPECTROSCOPY
CARBON DIOXIDE
CARBON MONOXIDE
CRYOGENICS
ELECTRODES
LASERS
MOLECULES
OZONE
PLASMA CHEMISTRY
RADIOWAVE RADIATION
SLABS