Direct nuclear pumping of a Ne-N2 laser

Abstract

Direct nuclear pumping of a Ne-N2 laser has been achieved with simultaneous output at two wavelengths (8629 and 9393 Å) in atomic nitrogen. Pumping was achieved through bombardment of the gas by MeV ions generated when neutrons from a TRIGA reactor interact with a boron-10 coating on the inner wall of the laser cell. Pressure, concentration, threshold, and other parameters are presented.

Distinguished celebration for Professor Georg H. Miley by the University of Illinois, Urbana, Illinois, USA

“…In contrast to this, the CO 2 laser was from the beginning based on gas discharges, but to apply electron beam excitation was first done by Miley and subsequently led to his pioneering excitation of excimer lasers by e-beam irradiation of noble gases mixed with fluorine (Miley, 1972). This gave him the way to establish the activities with his TRIGA research reactor in his Department of Nuclear Engineering at the University of Illinois to reach the first laser pumped with the neutrons from fission (DeYong et al, 1976) making him the father of the Nuclear Pumped Laser.…”

Stimulated emission due to infrared transitions in chlorine atoms in gaseous mixtures pumped by uranium fission fragments

“…[20]) that dissociative excitation by collisions of metastable helium atoms with molecular gases fills the upper active levels in low-pressure gas-discharge lasers based on the transitions in the C, N, and other atoms. It is pointed out in Refs [6,8] that this mechanism fails to account for the operation of lasers with He -CO 2 and Ne -Ne 2 mixtures since the energies of metastable He (or Ne) atoms are insufficient for the dissociation of CO 2 (or N 2 ) molecules and for the formation of C (or N) atoms in the upper active levels.…”

“…The maximum energy parameters (output radiation power up to 2.5 kW, efficiency l%-3%) and the lowest lasing thresholds (threshold thermal neutron flux F t ~ 10 13 cm" 2 s~') were reported for IR transitions in the Xe atom (A = 1.73, 2.03, and 2.6 um) when Ar-Xe and He(Ne)-Ar-Xe mixtures were excited by uranium fission fragments [2,4,5]. Less detailed studies have been made of nuclear-pumped lasers based on transitions in C [6,7], N [8], O [9], and Cl [10] atoms. A special feature of these lasers is that stimulated emission occurs as a result of transitions in atoms which are components of CO, CO 2 , N 2 , O 2 , and Cl 2 molecular gases, at a low (less than 0.1 Torr) concentration of the active component (molecular gas).…”

Comments About Nuclear-Pumped Laser Research in the United States

“…Then, in the search for lower thresholds the University of Illinois group discovered a new class of NPLs where lasing occurs in a minority species (i.e., "impurity" lasers). The first such laser used small concentrations of N 2 in neon [56]. Subsequently, a low-threshold (0.04 W/cm 3 pump power) laser was developed using carbon from the dissociation of CO and CO 2 during irradiation [57].…”