Influence of the modal composition of the radiation on the oscillation dynamics of a CO2-laser with a saturable absorber

The influence of the modal composition (transverse modes of a single longitudinal mode) of the laser radiation on the oscillation dynamics of a CO₂-laser with a saturable absorber in the cavity is investigated. Passive Q-switching in initiation of the fundamental mode TEM₀₀ and the modes of the first family TEM₀₁ and TEM₁₀ is considered. It is established that in the case of multimode oscillations sequences of single pulses with an irregular change in their amplitude can be observed. The multimode oscillations obtained are compared with similar single-mode oscillations, and their special features and differences are discussed. Reported at the Second International Scientific and Technical Conference on Quantum Electronics, Minsk, November 23–25, 1998. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 5, pp. 681–687, September–October, 1999.