100 W, 1 mJ, Sub-200 fs High Performance Laser Generation Using Cascaded Yb: CGA and Yb: YAG Amplification

We demonstrate a high-power solid-state femtosecond laser system based on two types of ytterbium (Yb)-doped gain media. This system effectively harnesses the advantages of Yb: CGA and Yb: YAG crystals: broad spectral output capability and power-scaling potential. The Yb: CGA regenerative amplifier achieved an output power of 80 W at a repetition rate of 100 kHz, with spectral full width at a half maximum (FWHM) of 10.2 nm. To the best of our knowledge, this is the highest average power output from a Yb: CGA regenerative amplifier. Subsequently, by cascading the two stages of Yb: YAG single-pass amplifications, the laser output power was increased to 121 W. Owing to the mismatch in the gain peaks between Yb: CGA and Yb: YAG, the amplified spectral FWHM broadens to 13.9 nm. After compression, the laser power and pulse width were 111 W and 184 fs, respectively. Notably, this is the first diode-pumped solid-state laser to achieve millijoule-level pulse energy, pulse widths below 200 fs, and average power exceeding 100 W using a hybrid gain medium amplification scheme.