Optimization of a UV Cu+ laser excited bypulse-longitudinal Ne-CuBr discharge

The discharge conditions for high average output power on four UV Cu⁺ lines at 248.6 252.9, 260.0, and 270.3 nm, in a nanosecond pulse-longitudinal Ne-CuBr discharge, have been investigated in two discharge tubes of different designs. A record average output power of 210 mW (and a peak pulse power of 1.7 W) on the 238.6-nm laser line, and of 270 mW for multiline operation has been obtained. An optical effect enhancing the 248.6-nm laser line power has been observed as the intensity of two Cu atom laser lines (510.6 and 578.2 nm) increases. It has been shown that the presence of Br atoms in the discharge leads to a fall of the Ne metastable density via Penning ionization and, hence, to a decrease of the Cu⁺ metastable density and an increase of the laser output