The location of the electrodes of a copper vapor laser (CVL) discharge tube in cold buffer zones, where there are no metal vapors, leads to the formation of a phantom current before the “breakdown”. This necessitates the evaluation of whether the phantom current is an additional factor limiting the energy characteristics and what is the mechanism of this limitation? It is shown that at the initial stage of pumping, the intrinsic capacitance of the discharge tube is charged up to the “breakdown”, which determines two processes during this period of time – the population of metastable states of copper and the generation of a phantom current, which occurs as a result of shunting of the intrinsic capacitance of the discharge tube by the cold buffer zone from the anode side of the discharge tube. The mechanism of phantom current generation and its role in limiting the energy characteristics of CVL are considered. The studies indicate two problems on the way to improve the energy characteristics of CVL and the direction of search for their solution: the first is high pre-pulse concentration of electrons in the active medium and the second is the generation of a phantom current caused by processes in the cold buffer zones.
copper vapor laser, phantom current, pulse pumping, frequency and energy characteristics
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