Gueorgii G. Petrash

Characteristics of pulsed discharges in copper bromide and copper HyBrID lasers

Comparative measurements of discharge electrical waveforms have been carried out with a Ne-H/sub 2/-CuBr laser, a Ne-CuBr laser, and a Cu HyBrID laser, each of the same size and geometry, and under the same conditions of excitation. From the general similarity of the electrical characteristics of the HyBrID laser and the Ne-H/sub 2/-CuBr laser, together with a reappraisal of the role of hydrogen, it is concluded that the main characteristics of these lasers (high efficiency, high average output power, and special features of their excitation pulse waveforms) can all be qualitatively explained if we assume that HBr and not hydrogen (molecular, atomic, or ionic) is the responsible agent which acts via the process of dissociative attachment of electrons to HBr during the interpulse period and during the early stages of the discharge current pulse.

1.3 W average power at 255 nm by second harmonic generation in BBO pumped by a copper HyBrID laser

We present the first report of SHG using a copper HyBrID laser. These results allow us to discuss the main factors that determine SHG of HyBrID laser output radiation in a BBO crystal.

Kinetics of excitation and physical processes in active media of copper-vapor and copper-bromide-vapor lasers

Kinetics of excitation and relaxation of atomic levels in active media of copper vapor lasers and copper bromide lasers were studied experimentally. Population densities of the copper atoms ground state, upper and lower laser levels, and some higher lying levels were measured with temporal and spatial resolution during the excitation pulse and interpulse period. The measurements were made for laser discharge tubes with an active zone of 2 cm in diameter and 40 - 50 cm of length. Main physical processes determining operation of the lasers are discussed. From the experimental results estimates of electron density and electron temperature are made. Comparison of kinetics in copper vapor laser and in copper bromide laser with and without hydrogen additives is given.

Long-lived sealed-off CuBr laser

Abstract Investigations on the life-time of a whole-heated sealed-off CuBr laser are reported. Keeping the bromine concentration low enough not less than 500 h of laser operation is already realizable. The decrease of laser power is due mainly to output windows pollution.

Influence of Cs on CVL operation

An attempt to explain the influence of Cs on pulsed copper vapor laser (CVL) operation is presented. The influence of Cs admixture on the processes of ionization and recombination in a discharge plasma used for excitation of the laser are considered.

Mechanism of pulsed inversion in a process of ion-ion recombination

Pulsed ion-ion recombination lasers can have high output power and efficiency if it will be possible to realize idealized mechanism of inversion suggested in our previous publications. How close it will be possible to come to realization of the idealized scheme depends on the proper choice of the active medium components (metal, buffer gas, electronegative molecule} as well as corresponding conditions of excitation and recombination. Some possible pairs of positive and negative ions of several metals with negative ions of Br, Cl, and I are discussed.

Ion r-m transition lasers: possible transitions

An analysis of available transitions for pulsed laser oscillation from the first resonance levels to the metastable levels (r-m transitions) in singly ionized atoms is presented. The characteristics of resonance and metastable levels and wavelengths of corresponding r-m transitions are given for 30 elements. Energy level diagrams are presented for 8 typical elements.

Possible systems for realization of an ion-ion recombination laser: recombination with negative ion of oxygen

Possible pairs of positive metal ions and negative ion of oxygen suitable for realization of efficient ion-ion recombination are considered. Predominantly populated by ion-ion recombination levels of several metal atoms are indicated. Possibility of population inversion creation and lasing on some transitions in metal atoms as well as development of efficient non-coherent radiation sources is discussed. Energy level diagrams illustrating positions of ii-resonances and transitions from the predominantly populated by ion-ion recombination levels are presented for 9 metal atoms.

Initial stage of discharge and its influence on characteristics of copper vapor lasers

The main processes during initial stage of pulsed discharge in copper vapor lasers including the operation of a cathode and discharge development in cold end zones of a discharge tube are considered. The importance of fast voltage rise, proper operation of the cathode and recombination processes in the cold zones is emphasized.

High-pulse-repetition-frequency CuBr laser

In the paper, we present new results of CuBr-laser study in a regular pulse mode with a high PRF and in a mode of modified double pumping pulses with PRF = 30 kHz. It has been shown a stable PRF over 500 kHz can be obtained.