Limiting pulse repetition rate in copper vapor lasers

Abstract

Two groups of processes which limit the rate-power characteristics of copper vapor lasers are examined. The first of these is related to the inadequate relaxation rate of the metastable states and accordingly their high prepulse concentration, which degrades the lasing pulse parameters. The second group of processes is initiated by the high prepulse electron concentration. It is shown that if the effect of the prepulse electrons is neutralized in pulse-periodic copper vapor lasers, then lasing starts up again in the next pulse within 1 µs after the preceding pulse stops. It is concluded that the rate of deexcitation of the metastable states is so high that it has no effect whatever on the lasing parameters in real gas-discharge lasers based on copper vapor or copper bromide vapor, and the prospects are opened up for attaining a lasing power of ∼10 kW/m with electron-beam pumping.