A compact cw HCN laser with high stability and power output

Abstract

A compact cw HCN laser has been developed with particular attention to the factors which affect stability and high power output. The laser uses a 1 meter long discharge in a 5 cm diameter temperature controlled tube. The addition of a large proportion of helium to the gas mixture leads to the production of high power output at elevated tube temperatures and perfectly clean operation for several tens of hours. A stable discharge is obtained by using a hot tantalum cathode in a cooled sidearm. The laser produces 20 mW of continuous output at 337 υm with a signal-to-noise ratio better than 100 in a total bandwidth of 30 kHz. The volumetric power output is 90 μW cm −3.