High-power, high-pressure IR Ar – Xe lasers

Investigations of high-pressure lasers on Ar – Xe mixtures pumped by electron beams and electroionisation discharges are reviewed. A new method of pumping laser transitions by an electroionisation discharge is proposed. The method uses the excited states of Xe atoms as the ground laser level. An electroionisation laser on the IR transitions of a Xe atom with a volume of the active region of 10 L and a pulse duration of 5 μs is developed on this basis. Its specific (up to 8 J L^-1) and absolute (up to 80 J) energy outputs exceed those of electric-discharge noble-gas lasers by more than one and two orders of magnitude, respectively. It is shown that the efficiency of conversion of the electric energy deposited in the discharge into laser radiation can be as high as 5%. The laser beam divergence obtained at output energies close to the maximum one is ~3 × 10^-5 rad. It is shown in principle that a repetitively pulsed Xe laser emitting at 1.73 μm with a specific energy output of 0.5 – 1.0 kW L^-1 and an efficiency of 2.0% – 3.2% can be created.