Efficient vacuum-ultraviolet lasing in barium vapor

Parametric lasing in the vacuum-ultraviolet range was investigated experimentally in barium vapor. Picosecond YAlO₃:Nd³⁺ laser pulses were frequency-converted to the ~180-nm range with an efficiency of 0.7%. The dependences of the conversion efficiency on the buffer gas pressure and on the position of the constriction of the pump radiation beam were studied. The principal factor limiting the efficiency under resonance conditions was found to be the Stark effect.