EXCITATION OF EXCIMER KRF LASER BY OPTICAL DISCHARGE IN THE FIELD OF IR LASER-RADIATION

The possibility of the F2 - Kr - He-mixture excimer laser excitation by an IR laser pulse during the process of optical discharge in the active medium has been studied. Calculations for the mixture F2:Kr:He = 3:75:1500 and 4:200:1500 excited by 20 - 150 ns pulses at the wavelength of 2.8 and 10,6 mum have been made. The propagation of the exciting pulse in F2 - Kr - He medium with allowance made for the absorbtion of IR laser radiation by electrons of the optical discharge plasma, coming about from the laser radiation, has been investigated. It is shown that it is possible to pump KrF laser by IR laser radiation with an efficiency of approximately 5%, if the IR radiation is focused by an optical system with a focus distance of 1 - 30 m and the peak intensity at the laser medium input is approximately 10 GW/cm2 (lambda= 2.8 mum) and 1 GW/cm2 (lambda= 10.6 mum).