Abstract

We report on an OPCPA system, which is seeded by a broadband Ti:Sa oscillator. and pumped by a frequency doubled high power picosecond Yb fiber amplifier. Temporal synchronized seed pulses within the Yb gain bandwidth are generated in a photonic crystal fiber. Fiber Bragg gratings spliced to the preamplifiers act as spectral filters to generate 100 ps long pulses. A two- stage birefringent pulse shaper is implemented to create a flat-top temporal pump pulse profile. Direct amplification of these pulses in large mode area fibers without using a stretcher and compressor provides significantly reduced complexity. The parametric amplifier is based on two BBO crystals. It delivers 35 fs, 53 µJ pulses corresponding to 1.1 GW peak power at 40 kHz repetition rate.

© 2010 Optical Society of America