Time-resolved population studies of a N₂ion laser

In order to examine the lasing characteristics of the N 2 ion laser excited by a fast discharge, time-resolved measurements of the gain for the 391.4 nm and 427.8 nm transitions were carried out. The temporal behaviour of the population densities of the laser lower levels were measured by means of the interferometric method. The time histories of the sidelight at the laser transitions, which reflects the relative upper level population, were also measured. On the basis of these experimental results, a fairly good explanation of the lasing characteristics of the two laser oscillations is given.