Time dependent CO2 laser operation in a system consisting of a laser, an optical discharge, and a reflecting surface

An experimental investigation was made of the conditions for time-dependent operation of cw and pulse-periodic CO₂ lasers in a system consisting of a laser, an optical discharge, and a reflecting surface. High-frequency (~ 0.1 MHz) and low-frequency (~ 100 Hz) intensity oscillations of the laser radiation were discovered. The high-frequency oscillations appeared when the optical length of the discharge was strongly modulated and the low-frequency oscillations were associated with an oscillatory motion of the discharge plasma in the region of a focus.