DocumentCode :
1056529
Title :
Molecular saturation and the criterion for passive Q switching
Author :
Oppenheim, Uri P. ; Kaufman, Yoram J.
Author_Institution :
Technion-Israel Institute of Technology, Haifa, Israel
Volume :
10
Issue :
7
fYear :
1974
fDate :
7/1/1974 12:00:00 AM
Firstpage :
533
Lastpage :
540
Abstract :
Rotational hole burning is known to be the main factor that determines saturation in molecular absorbers during a short pulse. Experimental results are presented that suggest that pulse transmission measurements, as opposed to CW transmission measurements, must be used in order to determine if a gas can be used as a saturable absorber in passive 
switching. Rate equations are developed for a five-state model to explain saturation in SF6 . This model is found to predict CW and pulse transmission through SF6 at various lines of the 10.4-μm band of the CO2 laser. A simplified model is developed for pulse transmission through saturable gases and is solved analytically for the peak of the pulse. It is found that the absorption coefficient of the absorber at the peak of the pulse is given by a simple expression, which leads directly to a new criterion for passive switching. An experimental test of this criterion is carried out for several mixtures of SF6 and He which act as saturable absorbers under varying conditions of irradiation. It is found that the transition from CW to pulsed operation is very sharp and occurs at a well-defined value of radiation intensity.
switching. Rate equations are developed for a five-state model to explain saturation in SF switching. An experimental test of this criterion is carried out for several mixtures of SFKeywords :
Absorption; Equations; Gas lasers; Gases; Laser modes; Optical pulses; Predictive models; Pulse measurements; Q measurement; Testing;
fLanguage :
English
Journal_Title :
Quantum Electronics, IEEE Journal of
Publisher :
ieee
ISSN :
0018-9197
Type :
jour
DOI :
10.1109/JQE.1974.1068202
Filename :
1068202
Link To Document :
