Low-voltage electron-beam-pumped lasing of CdS at atmospheric pressure

Lasing has been observed in CdS crystals in air at atmospheric pressure and at room temperature. The crystals were pumped with pulsed 20-kV electrons through a vacuum-tight, electron-permeable nickel film. Voltage threshold for lasing is reached for a 13-kV electron beam incident on the film and is about the same for the crystals in vacuum or air. Laser life at 20 kV is also the same for the two environments--about 10
⁶
pulses of 50-ns duration.