Wavelength-versatile graphene-gold film saturable absorber mirror for ultra-broadband mode-locking of bulk lasers.
An ultra-broadband graphene-gold film saturable absorber mirror (GG-SAM) with a spectral coverage exceeding 1300 nm is experimentally demonstrated for mode-locking of bulk solid-state lasers. Owing to the p-type doping effect caused by graphene-gold film interaction, the graphene on gold-film substrate shows a remarkably lower light absorption relative to pristine graphene, which is very helpful to achieve continuous-wave mode-locking in low-gain bulk lasers. Using the GG-SAM sample, stable mode-locking is realized in a Yb:YCOB bulk laser near 1 μm, a Tm:CLNGG bulk laser near 2 μm and a Cr:ZnSe bulk laser near 2.4 μm. The saturable absorption is characterised at an intermediate wavelength of 1.56 μm by pump-probe measurements. The as-fabricated GG-SAM with ultra-broad bandwidth, ultrafast recovery time, low absorption, and low cost has great potential as a universal saturable absorber mirror for mode-locking of various bulk lasers with unprecedented spectral coverage.
Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.
Jie
J
Ma
Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.
Guoqiang
G
Xie
School of Electronic Science and Applied Physics, Hefei University of Technology, Hefei 230009, China.
Peng
P
Lv
Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.
Wenlan
W
Gao
Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.
Peng
P
Yuan
Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.
Liejia
L
Qian
Max Born Institute for Nonlinear Optics and Ultrafast Spectroscopy, Max-Born-Str. 2a, D-12489 Berlin, Germany.
Uwe
U
Griebner
Max Born Institute for Nonlinear Optics and Ultrafast Spectroscopy, Max-Born-Str. 2a, D-12489 Berlin, Germany.
Valentin
V
Petrov
State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China.
Haohai
H
Yu
State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China.
Huaijin
H
Zhang
State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China.
Jiyang
J
Wang