Kr2F* fluorescence measurements of electron beam pumped KrF laser mixtures

Abstract

The time-dependent Kr2F* fluorescence and KrF* laser emission of an electron beam pumped KrF laser are measured for two gas mixtures, 89.7% Ar/10% Kr/0.27% F2 and 99.6% Kr/0.4% F2, at initial gas temperatures from 294 to 417 K and for pulse lengths >600 ns. The measurements indicate an inverse square root temperature dependence for the Kr2F* formation, which is weaker than earlier predictions. Analysis of the Kr2F* and KrF* data also indicates that electron quenching and the effects of gas heating during the pump pulse significantly affect the laser performance of the Kr/F2 mixture. Results of a model agree well with the data.

Electra: Repetitively pulsed, 500 J, 100 ns, KrF oscillator

“…As no enhancement of the laser en-ergy is observed, we conclude that the dependence of k 1 and k 2 on T g must be weak at the pressure of 20 psi ͑1.27 amagats at T 0 ). Previous examinations 17,18 of the temperature dependence in three-body relaxation destruction of KrF* using small heated cells with Ar rich mixtures found a weak dependence of the KrF* fluorescence at near 1 amagat density. However, at higher densities, the reduction of k 1 and k 2 at increased T g may be important.…”

Luminescence characteristics of the Kr2F* excimer molecules in (Kr-SF6) gas mixtures with a Low SF6 content upon pumping by a pulsed beam of fast electrons

“…The KrF* and Kr 2 F* excimer molecules are efficient transformers of the pump energy of krypton−fl uorine-containing gas mixtures into light and laser radiation of the ultraviolet (λ = 248 nm) and visible (Δλ ~ 400-500 nm) wavelength ranges [1][2][3][4][5][6]. The gas media used for these purposes are usually threecomponent high-pressure mixtures Ar-Kr or Ne-Kr with admixtures of a fluorine-containing donor, typically pure F 2 or NF 3 [4,7].…”

Fluorescence and transient absorption spectra of Ar/Kr/F 2 mixtures excited by e-beam

“…This will allow us more accurate accounting for some important kinetic reactions. In particular, of the formation of Kr 2 F molecules, which, firstly, characterizes one of the main quenching processes of the upper KrF laser level in threebody collisions with Kr and Ar atoms [4], and, secondly, is an absorber of KrF laser radiation that might significantly affect on the extraction efficiency of laser radiation from the gain medium. Besides early experiments [1,2], transient absorption in Ar/Kr/F 2 mixtures at 248-nm and several other excimer laser wavelengths was measured by using an effect of suppression of Kr 2 F fluorescence [5].…”

“…Amplitudes(1,3) and energies(2,4) of KrF (B→X) (1, 2) and Kr 2 F (4 2 Γ→1,2 2 Γ) fluorescence(3,4) in dependence on pressure of gas mixture.…”

“…Oscilloscope signals of gas fluorescence at 430-nm wavelength (1), its superimposition with the probe ISI-1 radiation (2), the difference signal (3), and normalized transient absorption(4).…”