Lasers electronic transitions

This alkalilike behavior of metastable noble-gas atoms effectively transforms the excitation energy of the metastable noble-gas atom into electronic energy of a rare-gas halide molecule with large reaction cross section. Because the electronically excited noble-gas halides have short radiative lifetimes and the ground-state noble-gas halides are not strongly bound, the process of formation of electronically excited noble-gas halides from metastable noble-gas atoms has been shown to be ideal for the operation of the electronic transition laser and has been successfully used in high-efficiency rare-gas halide lasers in recent years.21"23... 

H. H. Michels, Presented at the First Summer Colloquium on Electronic Transition Lasers, Univ. of Cal., Santa Barbara, June 17-19, (1974). 

The best prospect for creating a chemically driven electronic transition laser is to use a transition where the upper laser level is metastable. Chemical methods that generate high yields of certain metastables have been developed, but so far it has not been possible to achieve lasing on the primary products. For example, inverted populations of the metastables NF(a A) and NCl(a A) can be generated by chemical means, but the a A —... 

In this chapter, I will consider chemically pumped electronic transition lasers that are based on energy transfer from 02(a) or NX(a) metastables, focusing on the energy transfer and reaction kinetics of these devices. As the... 

C.A. Brau, J.J. Ewing, Spectroscopy, kinetics and performance of rare-gas halide lasers, in Electronic Transition Lasers, ed. by 1.1. Steinfeld (MIT Press, Cambridge, 1976)... 

The interest in chemiluminescent (CL) processes in the early 1970 s was fuelled by the need for efficient chemical light sources and above all for reactions capable of pumping an electronic transition laser. This programme did not meet with success since the CL yields of many reactions studied [1,10] were disappointingly low, and electronic inversions similar to those found in the decomposition of 12 dioxetanes [11] have not been found. It is timely therefore to inquire after the dynamical reasons for the monotonically decreasing, quasi-statistical electronic state distributions that have taken so many researchers by surprise. The answer is given in Sections 3,2 and 3.3 in terms of symmetry arguments. 

Summer Colloq. on Electronic Transition Lasers, Snowmass Village,... 

This review is organized as follows Section 3.2 presents a brief discussion of the HF(DF) and CO chemical lasers which are at present the most highly developed systems for practical applications Section 3.3 outlines recent uses of small chemical lasers in laboratory research and Section 3.4 is devoted to a general discussion of problems in the search for new chemical lasers, with particular emphasis on electronic transition lasers capable of operation at visible wavelengths. 

J. I. Steinfeld ed.. Electronic Transition Lasers, Proceedings of the Second Summer Colloquium on Electronic Transition Lasers, Woods Hole, Mass., 1975, MIT Press, Cambridge, Mass. (1976). 

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