We demonstrate the generation of up to the 63rd harmonic (lambda=12.6 nm) of a Ti:sapphire laser pulse (150 fs,10 mJ), using a prepulse- (210-ps, 24-mJ) produced boron plasma as the nonlinear medium. The influence of various parameters on the harmonic conversion efficiency was analyzed. The steep decrease in intensity for low-order harmonics (up to 19th order) was followed by a plateau. Typical conversion efficiencies were evaluated to be 10^-4 (for a 3rd harmonic) to 10^-7 (within the plateau region). Harmonic generation appeared to be efficient for the plasma that comprised neutral atoms and singly ionized boron.
© 2005 Optical Society of America
Rashid Ganeev, Masayuki Suzuki, Motoyoshi Baba, Hiroto Kuroda, and Tsuneyuki Ozaki, "High-order harmonic generation from boron plasma in the extreme-ultraviolet range," Opt. Lett. 30, 768-770 (2005)