Chirped pulse amplification based on praseodymium-doped fluoride fibers

We have developed a chirped pulse amplification system for ultrashort 1300 nm pulses based on praseodymium-doped fluoride fibers (Pr:ZBLAN). The 1300 nm seed pulse is generated through soliton-dispersive wave coupling in a highly nonlinear fiber pumped by a pulse from an erbium-doped fiber laser. The seed pulse is stretched with a grating stretcher to ∼150 ps and amplified with a two-stage Pr:ZBLAN amplifier. The average power reaches ∼112 mW at the repetition rate of 40 MHz. The pulse is compressed to 225 fs by using a pair of gratings without serious phase distortion.