DYNAMICS OF A TEA CO2-LASER WITH A CUBIC NONLINEAR MEDIUM IN THE CAVITY - FROM FREQUENCY STABILIZATION TO CHAOS

A method for controlling the frequency of radiation from a single-mode TEA CO2 laser with external signal injection was proposed, justified, and realised experimentally. This method made it possible to stabilise the output frequency of the laser (to within approximately 0.1 MHz) during the time interval of maximum power, i.e. during the leading spike. This was done by introducing a suitable nonlinear medium (InAs plate) into the laser cavity. The transition from a single-mode to a multimode lasing regime with regular and chaotic pulsations of the output power could occur because of internal injection excitation of adjacent transverse and longitudinal modes by radiation which was chirped due to the nonlinearity of the intracavity optical components even in the case of single-mode emission.