Nikola V. Sabotinov

Parametric study of the CuBr laser with hydrogen additives

A systematic investigation of the electric parameters of the CuBr laser plasma during the excitation pulse in their correlation to the laser output characteristics is presented. Based on the electric parameters, the temporal course is calculated of the electron density during the discharge. The authors offer a simple mechanism which generally explains how the hydrogen occurred in the copper vapor laser. The mechanism consists of shielding copper ionization by the process of electron detachment from negative hydrogen ions. >

Effect of hydrogen on CuBr laser power and efficiency

Abstract Addition of small amounts of hydrogen to the neon buffer gas in a CuBr laser causes doubling of the average output power and laser efficiency. An efficiency of 1% is easily obtained. Electrical parameters of the pulsed discharge as functions of the hydrogen additive pressure are reported.

Copper bromide laser of 120-W average output power

A Ne-H/sub 2/-CuBr laser (/spl lambda/510.6, 578.2 nm) is reported, which produced an average output power of 120 W at 2.5% efficiency (based on stored energy) and 100 W at 3% efficiency. These output power and efficiency figures are record values for copper bromide lasers. The sealed-off device produced maximum output power at a pulse recurrency frequency (PRF) of 17.5 kHz. Laser operating characteristics and electrical parameters are described.

A new circuit for CuBr laser excitation

A novel electrical circuit for CuBr laser excitation which consists of two interacting capacitive circuits is reported for the first time. An output power of 19 W with an efficiency of 1.6% was obtained. Some features of the laser operation, such as the voltage of the electrodes, the current pulse and the laser pulse, are given.

Temporal and radial evolution of the populations of CuI levels in the CuBr vapor laser

Populations of CuI ground state, resonance, and metastable levels have been measured in CuBr laser with and without hydrogen additives. Temporal evolution and spatial distribution populations have been studied during the excitation pulse and also during the interpulse period of time. Addition of hydrogen results in a smaller rate of resonance and metastable levels excitation and smaller depopulation of the ground state during the excitation pulse. Repopulation of the ground state after the excitation pulse with hydrogen is much faster. CuBr molecules have been detected only in the periphery of the active zone. The density of the CuBr molecules had no noticeable change either during the excitation pulse or in the interpulse period. >

Coil hollow cathode for metal vapor lasers

Abstract A coil hollow cathode for hollow cathode discharge lasers is developed. Increasing the distance between the windings of the coil the operating voltage of the discharge is increased.

UV lasing on Cu/sup +/ in a Ne-CuBr pulsed longitudinal discharge

UV lasing on copper ion transitions in CuBr vapor laser has been obtained in a nanosecond pulsed longitudinal discharge with Brewster windows and external mirrors. A record small-signal gain per unit length has been achieved (up to 19%/m and 16%/m for the 238.6- and 270.3-nm transitions, respectively). Infrared (IR) laser action on Cu ions in a He-CuBr discharge and on Ag ions in a He-AgI (silver iodide) discharge has also been observed. A maximum average output power of 430 mW has been achieved multiline (740.4-780.8 nm) on the Cu+ IR transitions. A maximal gain of 58%/m has been obtained on the strongest 780.8-nm transition.

Strontium atom laser excited by nanosecond pulsed longitudinal He-SrBr2 discharge

An investigation of a strontium bromide vapour laser excited by a nanosecond pulsed longitudinal discharge is presented. The optimal discharge conditions for laser oscillation on several Sr atom and ion lines are found. At multiline output an average laser power of 2.4 W is obtained, more than 80% of which is concentrated at the 6.45 µm Sr atom line.

Influence of the active zone diameter, on the UV-ion Ne-CuBr laser performance

An active-zone-diameter scanning of an ultraviolet (UV) Cu/sup +/ laser excited in a nanosecond, pulsed longitudinal Ne-CuBr discharge with an excitation pulse repetition frequency of 19.5-25 kHz is carried out. The discharge conditions for achieving a maximum average output power on the UV lines-248.6, 252.9, 260.0, and 270.3 nm are found for each active zone diameter. A record average output power of 1.3 W is obtained for multiline operation. The specific average output power is 57 mW/cm/sup 3/ at an active volume of 23 cm/sup 3/. The highest peak pulse power and average laser power on the 248.6-nm laser line for the UV Cu/sup +/ lasers are also measured-3.25 and 0.85 W, respectively. A simplified kinetic model, which describes the discharge afterglow processes, is made.

Influence on operating characteristics of scaling sealed-off CuBr lasers in active length

Abstract We have scaled sealed-off copper bromide lasers in average output power from 24 W to 58 W by increasing the active length from 50 to 120 cm. It was found that the increase in active length was accompanied by an increase in operating efficiency from 1.8 to 2.2%, and a reduction in power dissipated at the electrodes. A complex behaviour of laser output power on pulse recurrence frequency has been attributed to the influence of acoustic resonances on particle densities in the laser discharge. It was also found that the CuBr reservoir temperature must be increased as PRF is increased in order to maximize output power. The hydrogen partial pressure optimum for laser oscillation in our 40 mm discharge tubes was found to be twice that found in earlier studies in which the gas discharge was limited to 20 mm effective diameter.