Excitation and relaxation of metastable atomic states in an active medium of a repetitively pulsed copper vapour laser

Abstract

The influence of a pre-pulse population of copper atom metastable states and their sub-population at a current pulse edge on the copper vapour laser pulse energy is studied under optimal temperature conditions. Experiments have been performed with active elements of a commercial laser having an internal diameter of a discharge channel of 14 and . It is found that at a pulse repetition frequency of , corresponding to a maximal output power, the reduction of the energy due to a residual population of metastable states is by an order of magnitude less than due to their sub-population at a current pulse edge. The modelling based on the experimental results obtained has shown that in the case of an active element with an internal diameter of , a decrease in the pulse leading edge from to does not reduce the laser pulse energy up to the repetition frequency of at an average output power of and efficiency of .