Efficient generation of femtosecond pulses at 525nm has been demonstrated by the extracavity frequency doubling of the output of a diode-pumped femtosecond Yb:KYW laser using a periodically-poled LiTaO3 crystal. An average second harmonic power of 150mW was produced at nonlinear conversion efficiency of 43%. The temporal characteristics of the frequency-doubled pulses as a function of focusing conditions in a "thick" nonlinear crystal have been investigated experimentally and pulses as short as 225fs have been generated at a pulse repetition frequency of 86MHz.

© 2005 Optical Society of America

PDF Article