Pulsed He-Zn hollow cathode laser

Pulsed He-Zn hollow cathode laser is investigated. Simultaneous lasing on five visible Zn II (491.2 nn, 492.1 nm, 589.4 nm, 601.2 mm and 610.2 nn) and three infrared Zn II (747.9 mn, 758.8 nm and 775.8 nm) lines is obtained. Helical cofiguration of the cathode is used. The dependence of the laser output parameters on the excitation pulse: peak value, duration and repetition rate and He and Zn pressures is investigated. Optimal lasing is obtained at 6-9 A peak current, 5-8 Torr He pressure, 420-450 degrees C tube wall temperature and 13 mu s pulse duration. Stable operation and no change in the output power is observed by the variations of the excitation pulses repetition rate up to 1000 Hz. Laser gain values of more than 100 %/m for the Zn II 758.8 nm line, 30 %/m for the Zn II 492.4 nn line and 15 %/m for the 491.2 nn line are achieved.