Open AccessWS_2 saturable absorber for dissipative soliton mode locking at 106 and 155 µm
Author(s) -
Dong Mao,
Shengli Zhang,
Yadong Wang,
Xuetao Gan,
Wending Zhang,
Ting Mei,
Yonggang Wang,
Yishan Wang,
Haibo Zeng
Publication year - 2015
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.23.027509
Subject(s) - saturable absorption , tungsten disulfide , materials science , optoelectronics , fiber laser , dissipative soliton , optics , mode locking , graphene , femtosecond , laser , absorption (acoustics) , dispersion (optics) , dissipative system , soliton , wavelength , nanotechnology , nonlinear system , physics , quantum mechanics , metallurgy , composite material
Transition-metal dichalcogenides, such as tungsten disulfide (WS2) and molybdenium disulfide (MoS2), are highly anisotropic layered materials and have attracted growing interest from basic research to practical applications due to their exotic physical property that may complement graphene and other semiconductor materials. WS2 nanosheets are found to exhibit broadband nonlinear saturable absorption property, and saturable absorbers (SAs) are fabricated by depositing WS2 nanosheets on side-polished fibers. Attributing to the weak evanescent field and long interaction length, the WS2 nanosheets are not exposed to large optical intensity, which allows the SA to work at the high-power regime. The SAs are used to mode lock erbium- and ytterbium-doped fiber lasers with normal dispersion, producing trains of dissipative soliton at 1.55 and 1.06 µm respectively. Simulations show that the bandgap of WS2 nanosheets decreases from 1.18 to 0.02 and 0.65 eV by introducing W and S defects respectively, which may contribute to the broadband saturable absorption property of the WS2.