Electron-bm controlled discharge N/sub 2/O laser

Abstract

The pulsed electron-beam controlled discharge (EBCD) N20 laser is P.N.Lebedev Phys.Inst.,USSR Ac.Sci.,Leninslsy pr. 53,, Moscow, USSR investigated. The radiation energy, the specific output energy and the efficiency of this laser substantially exceed those known for the electric discharge N 2 0 lasers. The EBCD laser has been used with the /cm2. EBCD current pulse duration was I O -5 0~~. Laser gas pressure was 0.25 atm. The specific output energy and efficiency of the laser operating on gas mixture N20:N2:He = 3:20:27 were t u 1 J/l.atm and 2.5%. An addition of CO to the N20-N2-He laser mixture (or complete replacement of N2 with CO) enhanced not only the input energy, but also the energy parameters of the EBCD N20 laser by more than an order of magnitude. The enhancement of the energy input is explained by the process of associative detachment of electrons via the reaction : 0-+ CO -CO2 + E 9 where the 0-negative ions result reaction N20 + e-N2 + 0-. The output energy of tu15 J ( CU 30 J/1. atm ) and efficiency of 10 % ware obtained for the laser mixture N 2 0 : C0:He = 2:l4:9. Small signal gain is estimated to be much higher than 4 . 1 0 ' 3 cm-'. Typical generation pulse duration was about 10-30~as (T = = 300 K). A number of spectral lines and the wavelengths depended on the energy input, gas temperature and composition of the laser mixture.There were 4 laser lines from P(15) to P(18) at T W 2 2 0 K, for example.Laser generation was observed simultaneously on the CO2 and N20 laser transitions when adding CO2 to the laser mixture (N20: CO2 : CO : IT2: He 3 1.5:1.5:10:10:27).The dependence of EBCD N20 laser parameters on the laser mixture, temperature, and energy input were analyzed. active volume (U 2 1 (3.6~4.2~140 cm 3 ). E B current density was -2 0 mA/ from the 662