High-Power Fiber-Based Femtosecond CPA System at 1560 nm

We demonstrate a fiber-based, high-power, high-repetition rate chirped pulse amplification system operating at 1560 nm. The system is seeded by a graphene mode-locked Er-doped fiber laser with 50 MHz repetition rate. The all-fiber amplifier chain consists of three stages, out of which the last stage utilizes a large-mode area Er ³⁺/Yb ³⁺ co-doped fiber. In order to reduce the complexity of the system, the pulses are temporally broadened in a segment of inverse dispersion fiber. After amplification, the pulses are compressed in a two reflection grating-based compressor. The system provides 835 fs-short pulses with 8.65 W of average power. The demonstrated system, except of the compressor, is designed in all-fiber technology, providing robustness, compactness and environmental stability.