Spontaneous coherent pulsations in 339-m He–Ne standing-wave laser oscillators

Abstract

Spontaneous pulsations similar to the type discovered in 3.51-m Xe laser oscillators were reported several years ago in 3.39-m He-Ne lasers, but no numerical interpretation of the He-Ne data has been given. The model for the Xe laser instability is adapted here to the He-Ne system, and the results include direct comparisons between theoretical calculations and published experimental data. Good agreement is obtained for the instability threshold, the pulsation frequencies, and many other features; and unmeasured but potentially useful pulsation characteristics are also readily obtained from the model.

Stability criteria for spontaneously pulsing gas lasers

“…On the other hand, the corresponding instability in inhomogeneously broadened lasers can have a threshold that is very close to the lasing threshold. This effect has been studied many times since its discovery in Doppler-broadened xenon [1][2][3][4][5] and helium-neon [6][7][8] gas lasers, and it may be of practical value in applications requiring simple and efficient sources of periodic or chaotic optical pulsations. Thus, it would be useful to have as detailed an understanding as possible of the experimentally accessible laser instabilities.…”