1 mJ, 380 fs ultrashort pulses from an Yb:YAG single crystal fiber power amplifier

摘要

In the context of ultrashort pulse amplification, Single Crystal Fibers (SCF) provides several advantages that clearly benefit to the amplification of ultrashort and intense pulses. Among them, the mitigation of non-linear effects thanks to the short length of interaction together with the large beam diameter is probably the most interesting compared to rod-type amplifier. The crystalline structure provides ten times higher thermal conductivity than glass. In addition, the high gain per pass prevents the use of a regenerative amplifier and therefore significantly expands the range of operation at a high repetition rate. In a previous proof-of-principle experiment, femtosecond pulses were directly amplified from 400 mW to 12 W average power in a two-pass architecture while maintaining the duration of the 30 MHz repetition rate pulses below 400 fs [1]. In this work, we use a chirped pulse amplification system which allows to reduce the repetition rate and obtain much higher energies per pulse [2].