Efficient femtosecond optical parametric generator with a birefringent delay compensator.
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.
Chen
Y C
YC
Fang
X J
XJ
Li
J
J
Liang
X Y
XY
Zhang
H L
HL
Feng
B H
BH
Zhang
X L
XL
Wu
L A
LA
Xu
Z Y
ZY