Two-beam pumped infrared femtosecond nondegenerate optical parametric amplifier

We demonstrate a two-beam pumped infrared femtosecond (fs, 10−15 s) broadband nondegenerate optical parametric amplifier (OPA). Compared with one-beam pumped femtosecond OPA, the output pulse energy is promoted relatively, and the broadband amplified pulse spectrum and pulse duration from the two-beam pumped infrared femtosecond OPA are similar. Though the two femtosecond pump beams are coherent and interferential with each other, the near field of the output beam is smooth and close to the Gaussian figuration. The results demonstrated that two pump sources can be used in the femtosecond OPA instead of one pump source for a combined higher pump energy and relative higher OPA amplified pulse energy with broadband femtosecond pulse duration.