O. L. Gaiko

New operation regimes of a CO2 laser with intracavity saturable absorber

Abstract New operation regimes of a CO 2 laser with CH 3 OH vapour as intracavity saturable absorber have been realized experimentally. The time evolution of the laser output power may be interpreted by the heteroclinic orbits in the phase space around two, three and more fixed unstable points with intensities different from zero.

Alpha 5.28 and 81 MHz discharge of a planar geometry for CO2 slab lasers and plasmachemistry

A capacitively coupled planar rf discharge in CO2/N2/He gas mixtures at pressures up to 50 Torr is investigated using optic emission spectroscopy methods. The spatial distribution of the gas kinetic temperature has been measured and the mechanisms of the heating of plasma’s neutral component in various zones of the electrode gap have been considered. The influence of small additives of water vapor on luminescence intensity and plasma parameters is also discussed.

Giant pulsed molecular laser for plasma diagnostics

where i is wavelength of the probe radiation; 8 is the scattering angle; k D = (Te/4~nee2) I/2 is the Debye radius; ne, T e are the electron concentration and temperature; e is the charge of the electron. For e > i corresponds to collective radiation scattering, and analysis of its spectrum allows the ion temperature to be measured, independently of electron concentration, and plasma oscillations and instabilities to be studied. As is evident from the expression for ~, using lasers for diagnostics in the visibie and IR regions of hot plasma (T e -~ 1 KeV) with moderate density (n e = 10• cm -3) collective processes can only be observed with small scattering angles, which prevents localized measurements and makes the detection of useful signals difficult. Switching to a laser in the submiiiimeter (SVIM) region allows operation at angles up to ~/2 (which significantly increases spatial resolution) and allows heterodyne methods of detection to be used. Furthermore, the scattered power is proportional to the square of the wavelength of the probe radication, whch eases detection.