EFFICIENT EXTREME UV HARMONICS GENERATED FROM PICOSECOND LASER-PULSE INTERACTIONS WITH SOLID TARGETS

The generation of high harmonics created during the interaction of a 2 .5 ps, 1053 nm laser pulse with a solid target has been recorded for i ntensities up to 10(19) W cm(-2). Harmonic orders up to the 68th at 15 .5 nm in first order have been observed with indications up to the 75t h at 14.0 nm in second-order diffraction. No differences in harmonic e mission between s and p polarization of the laser beam were observed. The power of the 38th high harmonic at 27.7 nm is estimated to be 24 M W.