Ultrashort pulses, of the same time duration as the pump pulse, have been obtained with a traveling-wave parametric generator employing a temperature-tuned lithium triborate crystal in noncritical phase matching. Starting from a 190-fs pulse at 0.6 µm generated by a dye laser, we achieved an overall conversion efficiency of 10–15% in the tuning range 0.85–0.97 µm (and the corresponding range of 1.6–2.1 µm) with a pump energy of only 30 µJ. The easy operation in the femtosecond regime and the minimal energy requirements that we found are due to the small group-velocity mismatch of lithium triborate at this pump wavelength and to the absence of walk-off.
© 1993 Optical Society of America
G. P. Banfi, R. Danielius, A. Piskarskas, P. Di Trapani, P. Foggi, and R. Righini, "Femtosecond traveling-wave parametric generation with lithium triborate," Opt. Lett. 18, 1633-1635 (1993)