Импульсный индукционный CO-=SUB=-2-=/SUB=--лазер с энергией излучения 1 J и высоким КПД с ВЧ возбуждением

An efficient pulsed gas-discharge inductive CO2-laser with a radiation energy of 1.05 J has been developed for the first time. In this case, the pulse duration of the laser radiation was about 10 msec. The maximum efficiency of 21.1% was obtained at a radiation energy of 340 mJ. RF current pulses propagated along the inductor conductor and, thus, an inductive discharge was formed to create an inverse population at the infrared (IR) transitions of CO2* molecules. The temporal and energy characteristics of the radiation of the inductive CO2-laser depending on the duration of the pump pulse are investigated. The spatial characteristics and spectrum of the radiation of the developed laser are estimated. The divergence of the laser radiation was 0.52 mrad. The cross-sectional dimension of the laser output beam was about 35 mm in diameter.

Controlling the breakdown delay time in pulsed gas discharge

In experiment and 2D3V PIC MCC simulations, the breakdown development in a pulsed discharge in helium is studied for U=3.2 kV and 10 kV and P=100 Torr. The breakdown process is found to have a stochastic nature, and the electron avalanche develops in different experimental and simulation runs with time delays ranging from 0.3 to 8 μs. Nevertheless our experiments demonstrate that the breakdown delay time distribution can be controlled with a change of the pulse discharge frequency. The simulation results show that the breakdown process can be distinguished in three stages with a) the ionization by seed electrons, b) the ions drift to the cathode and c) the enhanced ionization within the cathode sheath by the electrons emitted from the cathode. The effects of variation of seed electron concentrations, voltage rise times, voltage amplitudes and ion-electron emission coefficients on the breakdown development in the pulsed gas discharge are reported.