High-efficiency Watt-level picosecond pulse generation based on Yb:Gd3AlxGa5−xO12 crystal

• A novel disordered Yb:GAGG laser crystal.
• Passive mode-locking performances of Yb:GAGG crystal was investigated by using a SESAM for the first time.
• High-efficiency Watt-level picosecond pulse generation was obtained.

A diode-pumped passively mode-locked Yb3+:Gd3Al0.5Ga4.5O12 (Yb:GAGG) laser has been investigated by using a semiconductor saturable absorber mirror (SESAM) for the first time. Pulses with duration of 1.6 ps were produced at the central wavelength of 1027.8 nm. At the absorbed pump power of 8.4 W, the maximum average output power of 1.02 W was obtained with the repetition rate of 45 MHz. The corresponding single pulse energy and the peak power were calculated to be 22.7 nJ and 14.2 kW, respectively.