title: Efficient femtosecond optical parametric generator with a birefringent delay compensator.
abstract: A novel method based on a birefringent crystal is presented to compensate for the group-velocity mismatch between a femtosecond pulsed pump and the signal or idler in an optical parametric generator (OPG). With a thin calcite plate inserted between two beta-barium borate crystals for synchronization, an efficient four-pass OPG pumped by a frequency-doubled ~200-fs Ti:sapphire laser is obtained. The conversion efficiency is almost doubled throughout the whole tunable region compared with a conventional OPG pumped at the same power density, indicating that the total conversion efficiency of femtosecond optical parametric amplifier system can be raised significantly by use of this new four-pass OPG to generate the seed.
authors: Y C
authors: YC
authors: Chen
authors: X J
authors: XJ
authors: Fang
authors: J
authors: J
authors: Li
authors: X Y
authors: XY
authors: Liang
authors: H L
authors: HL
authors: Zhang
authors: B H
authors: BH
authors: Feng
authors: X L
authors: XL
authors: Zhang
authors: L A
authors: LA
authors: Wu
authors: Z Y
authors: ZY
authors: Xu