Efficient stimulated emission from a microwave-pumped XeCl laser

An XeCl excimer laser excited by nanosecond microwave pulses of up to 500 MW was assembled. The optimal mixture in terms of lasing efficiency was found to be Ne:Xe:CCl₄ = 300:60:1 at a total pressure of 1.5 atm. The coefficient of energy coupling of the incident microwave power into the discharge plasma was ~ 70%. The maximum efficiency was 5.3% when the resonator length was 70 cm and the specific microwave pump power was ~ 1 MW/cm³. It was found that, in terms of the power deposited in the medium, the lasing efficiency was no lower than that under electron beam pumping and the total efficiencies in these cases could be comparable.