Les lasers moléculaires ultraviolets à excitation électronique transverse

Abstract

2014 Les plus récents développements des lasers moléculaires ultraviolets, à excitation électronique transverse sont présentés et analysés. Ces lasers peuvent être regroupés en deux familles caractérisées par le type de transition à partir de laquelle a lieu l'émission stimulée : transitions entre deux états liés et transitions entre un état supérieur lié et un état inférieur répulsif. Le second type offre des possibilités et laisse prévoir des performances supérieures à celles du premier, mais celles-ci ne sont pas encore toutes exploitées. Est également présenté l'état actuel de la technologie de ces lasers. Son développement permet de disposer de montages bien adaptés à un certain nombre d'applications. Un autre avantage est constitué par la possibilité de disposer de plusieurs raies lasers par simple changement du milieu gazeux excité. Enfin, les rendements d'émission élevés obtenus dans plusieurs cas expliquent l'intérêt porté sur les deux plans : théorique et expérimental. Abstract. 2014 The more recent developments of ultraviolet molecular laser, with transverse electronic pumping, are presented here. It is show that two models of electronic transitions : bound-bound and bound-unbound transitions, are in the beginning of the most part of intense ultraviolet laser lines. The second model offer some possibilities of stimulated emission which are not all worked. We point out, in the last part of this paper, some molecules from which laser lines should be possible. So, we analyze the state of the laser technology development. This has lead to realize several systems from which it is possible to have numerous laser lines with just changing the gases. As a practical consequence, may applications exist.

Spectral Analysis of the Amplified Spontaneous Emission in the Second Positive System of the N2 Molecule

“…From the theoretical point of view, some authors have already modelled the ASE action in the nitrogen UV transition, some with simpler premises, 10,11 others with more sophisticated models 12 and others including ionization effects in the active medium. 13…”

“…This system, lately known as transversely excited (TE), has become the most widely used in the production of nitrogen ASE systems, being extensively developed in many different ways. [7][8][9] From the theoretical point of view, some authors have already modelled the ASE action in the nitrogen UV transition, some with simpler premises, 10,11 others with more sophisticated models 12 and others including ionization effects in the active medium. 13 However, another interesting point with respect to the gain in this transition is the fact that the gain varies as a function of the rotational branch and the value of the quantum number J within each branch.…”