Diode-pumped Yb,Y:CaF2 laser mode-locked by monolayer graphene

• The monolayer graphene absorber with a sandwich structure was fabricated by CVD.
• The graphene absorber with high quality was tested and characterized.
• The Yb,Y:CaF2 laser mode-locked by graphene absorber was realized for the first time.

The large-area and high-quality monolayer graphene saturable absorber with a sandwich structure is prepared by the chemical vapor deposition technique. Using graphene saturable absorber, the mode locking operation of a diode-pumped Yb,Y:CaF2 laser is demonstrated. Without extra negative dispersion elements, 4.8 ps pulses are yielded at 1051 nm. The pulse repetition rate is 60 MHz.