Amplification of 1.08 GHz repetition rate femtosecond laser pulses to 97 W average power by a fiber amplifier

We demonstrate a femtosecond Yb:fiber laser amplification system which delivers 97 W average output power at a repetition rate of 1.08 GHz using a rod-type photonic crystal fiber. The re-compressed output pulse is 233 fs. Numerical simulation was also conducted in agreement with our experimental results.