Michail S. Yur'ev

Experimental and computer investigations of slab waveguide rf-excited CO2 laser

Results of investigations of a slab waveguide rf-excited carbon-dioxide laser are presented. Laser output power of range 200 W and efficiency about 10% in a beam with near-diffraction- limit divergence has been achieved. In the repetitive-rate mode, the pulsed power was more than twice as much as the average one in the cw mode. After beam shaping telescope, the total beam divergence of 2 - 3 mrad at the 0.8 power level has been obtained. A codes package of computer simulation of cw slab rf-excited diffusion-cooled carbon-dioxide laser was created. Comparison of calculated and experimental data has been fulfilled.

Instability of transverse laser beam profile in pulsed CO 2 lasers: a review

A review of papers devoted to investigation of instability in transverse laser beam profile with respect to amplitude-phase perturbations in pulsed CO2 lasers is presented. Experimental and theoretical investigations in this field and methods for instability suppression are described.

Slab waveguide high-power pulsed rf-excited CO2 laser

Slab RF-excited pulsed CO2-laser with the pumping frequency F equals 152 MHz, pulse duration in the range of 20 divided by 50 microsecond(s) , and pulse repetition rate f up to 100 Hz has been investigated. Output power, temporal shape of laser pulses, laser beam divergence were measured at the pumping power up to 400 W/cm3. Pulsed output power was varied in the range of 2 divided by 5 kW. The package of numerical simulation codes of pulse-repetition mode of slab CO2 laser was created. It is shown that the maximum input power is significantly increased by the change of excitation frequency from 80 up to 150 MHz. The measured and numerical data are compared.

Repetitively pulsed slab waveguide rf-excited CO2 laser

Research and development of pulsed-repetitively slab rf- excited carbon-dioxide laser is presented. The experiments were carried out for two modes operation: meander mode (duty factor delta equals 50%) and pulse repetition mode at delta equals 12.5%. The range of 240 divided by 4000 Hz of pulse repetition frequency was used. Pulse power about 400 W for meander mode and up to 700 W for the second mode have been obtained. Input power, radiation pulse shape and output beam divergence were measured.

Fine-scale thermal self-action of laser radiation in pulsed excimer lasers

The fine-scale thermal self-action of the laser radiation in pulsed excimer lasers is shown. The increments of the convective instability are obtained. The range of transverse modulation periods is defined, for which the instability exhibits significant temporal growth. It is shown that this effect can increase the laser divergence.

Computer simulation of rf-excited diffusion-cooled slab CO2 laser

A codes package of computer simulation of rf-excited cw slab carbon-dioxide laser with diffusion-cooling and hybrid waveguide-unstable resonator is presented. The package consists of four main parts: (1) structure of rf-discharge, (2) processes of inversion formation, (3) laser radiation propagation throughout the resonator, and (4) plasma chemical reactions in the active medium. The calculations of gain, output power, and near- and far-field patterns have been carried out. Comparison of calculated and experimental data has been fulfilled.

Phase conjugation for pulse-repetition CO2 laser with millisecond pulse duration

The results of the theoretical and experimental study of four-wave mixing of repetitively pulsed CO2 laser radiation is discussed. The PC-cell with the water-cooled mirror is used. Toluene and Xe-SF6 gas mixture are used as nonlinear media.