Multijoule performance of the photolytically pumped XeF(C→A) laser

An XeF(
C \rightarrow A
) laser with output up to 5.8 J/pulse has been demonstrated. The photolytic pumping scheme begins with
e
-beam excitation of xenon to produce Xe*
2
fluorescence at 172 nm. This VUV radiation is transmitted through an array of CaF
2
windows into the laser cell, where it photodissociates XeF
2
to produce primarily XeF(
B\frac{1}{2}
). Collisions with N
2
buffer gas relax the excited states to XeF(
C\frac{3}{2}
), which lases on a transition centered at 481 nm and continuously tunable over more than ±35 nm. Typical values of the experimental parameters were as follows. The 420 kV, 1 m
e
-beam source delivered an average current of 10 A/cm
²
over an aperture 14 × 100 cm for pulse lengths up to 1 μs. Total
e
-beam energy available was 3.5 kJ, of which 2.4 kJ was deposited in the xenon. The total VUV energy radiated was 720 J, of which 115 J was coupled into the laser cell. This produced 32 J of available XeF* energy, of which up to 18 percent was extracted as laser energy. The total system efficiency was 0.2 percent. Optimized designs should achieve better than 1 percent efficiency.