Precise Measurements on Optical Bistability and Passive Q- Switch in a CO2 Laser with Saturable Absorber

The laser with intracavity saturable absorber (LSA) is an interesting system in quantum optics because by the choice of the gain and the absorption "of the intracavity media, several different non linear phenomena can be realised. Optical bistability has been investigated quantitatively by Ruschin and Bauer in a CO2 laser with SF . Recently a large interest arose owing to experimental observations and the development of precise theoretical models. Passive Q-switch (PQS) consists of an operation with undamped spikes in the output power, a self pulsing behaviour produced by the instability of the continuous wave state and is a phenomenon of growing interest from an experimental as well as theoretical point of view2.