Vi. Igoshin et Rr. Letfullin, Diffractive focusing of an input pulse and giant energy gain in a laser based on an auto-wave photon-branched network, QUANTUM EL, 29(1), 1999, pp. 37-42
The wave approximation is used to analyse the energy parameters and the spa
tiotemporal behaviour of the electromagnetic field in a pulsed chemical las
er based on a photon-branched chain reaction in an unstable telescopic cavi
ty with an input coupling aperture through which the reaction is initiated
by IR radiation in a gaseous disperse medium composed of H-2, F-2, O-2, He,
and Al particles. It is shown that diffractive multifocal focusing of a pl
ane input wave, ensuring minimisation of the initially excited volume and a
correspondingly strong reduction (down to microjoules) of the required inp
ut pulse energy, occurs in the range of small input aperture diameters d(0)
= (3-30)lambda. A giant energy gain of similar to 3 x 10(9) can be reached
as a result of this optical effect and also because of auto-wave propagati
on of a photon-branched chain reaction throughout the whole volume of the l
aser. This giant gain makes it possible to construct a self-contained laser
with a kilojoule output energy, which can be initiated by microjoule input
pulses.