Coherent 70.9-nm radiation generated in neon by frequency tripling the fifth harmonic of a Nd:YAG laser.

We have produced coherent radiation in the XUV region at 70.9 nm by frequency tripling the fifth harmonic of Nd:YAG laser radiation in neon. BaB(2)O(4) was used to generate the fifth harmonic at 212.8 nm with an output pulse energy of 20 mJ and a pulse width of 5 nsec. Subsequent frequency tripling in neon gas generated 10 W of peak power at 70.9 nm.