Ultra-broadband nonlinear saturable absorption of high-yield MoS2 nanosheets.
High-yield MoS2 nanosheets with strong nonlinear optical (NLO) responses in a broad near-infrared range were synthesized by a facile hydrothermal method. The observation of saturable absorption, which was excited by the light with photon energy smaller than the gap energy of MoS2, can be attributed to the enhancement of the hybridization between the Mo d-orbital and S p-orbital by the oxygen incorporation into MoS2. High-yield MoS2 nanosheets with high modulation depth and large saturable intensity generated a stable, passively Q-switched fiber laser pulse at 1.56 μm. The high output power of 1.08 mW can be attained under a very low pump power of 30.87 mW. Compared to recently reported passively Q-switched fiber lasers utilizing exfoliated MoS2 nanosheets, the efficiency of the laser for our passive Q-switching operation is larger and reaches 3.50%. This research may extend the understanding on the NLO properties of MoS2 and indicate the feasibility of the high-yield MoS2 nanosheets to passively Q-switched fiber laser effectively at low pump strengths.
State Key Laboratory of Luminescent Materials and Devices, Guangdong Engineering Technology Research and Development Center of Special Optical Fiber Materials and Devices, and Guangdong Provincial Key Laboratory of Fibers Laser Materials and Applied Techniques, South China University of Technology, Wushan Road 381,Guangzhou 510641, People's Republic of China.
Rongfei
R
Wei
Hang
H
Zhang
Zhongliang
Z
Hu
Tian
T
Qiao
Xin
X
He
Qiangbing
Q
Guo
Xiangling
X
Tian
Zhi
Z
Chen
Jianrong
J
Qiu