Fyzikální ústav Akademie věd ČR

Investigated with a financial support of the US Air Force Research Laboratory, Kirtland AF Base, NM, USA, via the Grant of the USAF EOARD (European Office for Aerospace Research and Development) (see Projects)

Experimental and theoretical research on discharge generation of atomic iodine (Discharge Atomic Iodine Generator) for a COIL (Chemical Oxygen-Iodine Laser) and DOIL (Discharge Oxygen-Iodine Laser)

A plasmachemical method of atomic iodine generation (DAIG) for a COIL and DOIL was suggested as alternative to conventional method of molecular iodine dissociation. This method utilizes a decomposition of suitable iodine donor compounds by means of RF discharge. The original process is based on I atoms generation directly in the iodine injector serving also as a discharge chamber, which facilitates very fast injection of generated atomic iodine into the O₂(¹Δ) flow in laser. Gaseous alkyliodides CH₃I and CF₃I, and HI were used as iodine donors. Concentration of generated I atoms, measured in a region of the laser resonator by special diagnostics, was up to 2.5 x 10¹⁴ cm^-3. This would be sufficient for lasing even though a maximum dissociation fraction of all donors did not exceed 20% under given conditions. Further increase in dissociation efficiency is expected after optimization of discharge and gas flow conditions. Theoretical estimation of recombination of generated iodine atoms were performed by a developed kinetic model. This alternative method of atomic iodine generation should simplify an iodine system in the COIL laser operation and will be also convenient in combination with a discharge generation of singlet oxygen for a discharge oxygen-iodine laser (DOIL).