Nicolai G. Basov

60 J quasistationary electroionization laser on Xe atomic metastables

A high-pressure (p = 3.5atm) electroionization laser operating on the5d-6pxenon atomic transitions is investigated for a pumping pulse duration range up to 30 μs. An output energy of more than 60 J has been achieved with an Ar-Xe mixture and an active volume of 10 1. The angular divergence of the radiation was about5 times 10^{-5}rad. The advantages of such laser systems for industrial use is discussed.

Powerful electroionization laser on Xe infrared atomic transitions

A powerful pulsed high-pressure Ar-Xe laser with an active volume of 91 is studied. Laser output energies of 5.8 J for electron-beam pumping and 19 J for electroionization pumping are attained. The laser power exceeds 13 MW. More than 95 percent of the output laser energy is concentrated in the line with lambda = 1.73 mu m. Efficiencies greater than 5 percent were observed.

Heating of Laser Plasmas for Thermonuclear Fusion

In this survey the experimental results of the investigation of the laser produced plasmas in a wide interval of energy and light pulse duration are reported. The processes taking place at a dense plasma heated by laser radiation for the obtaining of a thermonuclear yield have been analyzed. The directional motion for heating in the various schemes using cumulative effects is discussed.

High-power electroionization CO 2 and CO lasers for industrial applications

This paper describes the evolution of a concept for a technological laser for industrial use. It consists of a collation of texts published by the authors and their colleagues in the U.S.S.R. over the past decade. A laser system which can run on multiple wavelengths, operate in CW, and long or short repetitive pulse modes, and which can operate economically was the design goal. Each section of this paper addresses one of the problems to be solved and indicates how it was solved. The end result is a laser system which uses a coupled turbocompressor and refrigerator to supply the gas flow and temperature control. The gas which expands and cools in the refrigeration turbine also supplies a portion of the power required by the turbocompressor. This system can operate on CO or CO 2 , thus serving as a source of mid-and far-infrared radiation in either the CW or pulse repetition mode. A five gas mixture (to conserve helium) and a silica gel gas purifier (in place of a catalytic converter) are proposed for their economic advantages.

Semiconductor streamer lasers

A new method of electrically exciting generation of light behind the ionization front in streamers is theoretically and experimentally considered. Light intensity of sim 10^{9} W/cm2was generated in Cd x Se 1-x and ZnSe crystals from radiation regions having characteristic dimensions of sim5 mu m, and moving with velocities sim3.10^{8} cm/s.

Laser system for aircraft takeoff and landing - "Glissada"

Measurements made against a stationary target at 700 m showed a 1-u range resolution of 10 cm. The signal processing following the photodetector-preamplifier consists of a video amplifier. threshold detector incorporating a constant-fraction (CF) discriminator, automatic range gating, and last-pulse selection. A portion of the transmitted laser pulse is coupled into the photodetector so that both the start and stop pulses undergo the same propagation delays. Range information is obtained in BCD form from a HP 5360A time-interval counter. For the initial flight tests, the three least significant decades of the counter (the least significant bit was 1 ns) were fed into a D/A converter to provide an analog output to a strip-chart recorder and a magnetic tape recorder. The magnetic tapes were subsequently digitized to facilitate the generation of terrain profiles. Numerous flight profiles were obtained, including some over deciduous and evergreen trees, cornfields, asphalt roads, and grassy fields. One typical profile is shown in Fig. 1. The profiles indicate high resolution and excellent discrimination. Profiles over forests showed interspersed ground and treetop returns. In case of multiple over-threshold returns, the last-pulse logic selects the ground return. The oscilloscope photographs allow examination of the detailed structure ofthe return. The noise amplitude over flat terrain was less than the 15 cm (1 ns) quantization level. Evaluation of these data is continuing.