2 GHz repetition-rate femtosecond blue sources by second harmonic generation in a resonantly enhanced cavity

We report a 2 GHz repetition-rate, all-solid-state femtosecond blue source. Pumped by a 740 mW femtosecond Ti:sapphire laser with the same repetition rate, 150 mW femtosecond pulses at 409 nm can be efficiently generated from the external resonant cavity with a lithium triborate crystal. (C) 2005 American Institute of Physics.