Open AccessGraphene/WS2 heterostructure saturable absorbers for ultrashort pulse generation in L-band passively mode-locked fiber lasers
Author(s) -
Wenxiong Du,
Heping Li,
Changyong Lan,
Chun Li,
Jùnwén Lǐ,
Zhuang Wang,
Yong Liu
Publication year - 2020
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.390949
Subject(s) - ultrashort pulse , materials science , saturable absorption , laser , dissipative soliton , optics , fiber laser , optoelectronics , dispersion (optics) , pulse duration , graphene , raman spectroscopy , mode locking , soliton , wavelength , physics , nonlinear system , nanotechnology , quantum mechanics
Graphene/WS 2 (G/WS 2 ) van der Waals (vdW) heterostructures are utilized as saturable absorbers (SAs) in compact mode-locked fiber lasers operating in the telecommunication L-band for the first time. The interlayer coupling is confirmed by Raman and photoluminescence spectra. In comparison with pure WS 2 , the heterostructure exhibits excellent nonlinear optical properties in terms of larger modulation depth and lower saturation intensity due to the strong interlayer coupling. By incorporating the G/WS 2 -based SA into an all-anomalous-dispersion fiber laser, stable conventional-soliton pulses with a pulse duration down to 660 fs can be realized at 1601.9 nm, manifesting better output performance compared to pure WS 2 . In addition, through shifting the cavity dispersion to the net-normal dispersion, the G/WS 2 SA can also be applied for dissipative-soliton generation. Resultant output pulses feature the central wavelength of 1593.5 nm and the pulse duration of 55.6 ps. Our results indicate that the G/WS 2 vdW heterostructure is a promising candidate as SA for pulsed laser applications, which pave the way for the development of novel ultrafast photonic devices with desirable performance.