Generation of Bright-Dark Soliton Pairs in Mode-Locked Fiber Laser Based on Molybdenum Diselenide

Abstract

In this paper, molybdenum diselenide (MoSe2) was fabricated by chemical vapor deposition (CVD) with a modulation depth of about 7.3% and nonsaturable loss of about 30.6%. Bright-dark soliton pairs have been obtained in a thulium-holmium-doped fiber ring laser based on MoSe2 as a saturable absorber (SA) for the first time, to the best of our knowledge. The results not only prove that MoSe2 can be used as an excellent saturable absorber in the field of ultra-fast optics, but also provide a certain reference value for the future research on bright-dark soliton pairs based on two-dimensional materials. INDEX TERMS molybdenum diselenide, bright-dark soliton pairs, mode-locked fiber laser. XIAOFA WANG received the Ph.D. degree from the School of Optoelectronic Engineering, Chinese Academy of Sciences, Beijing, China, in 2012. He is currently an Associate Professor with Chongqing University of Posts and Telecommunications, Chongqing, China. He has authored or coauthored more than 20 journal articles. His current research interests include fiber lasers, solid-state lasers, and nonlinear optics. He is a member of the Optical Society of America. HUIHUI HAN is currently pursuing the M.S. degree with the School of Optoelectronic Engineering, Chongqing University of Posts and Telecommunications, Chongqing, China. Her research interests include fiber lasers and nonlinear optics. DONGXIN LIU is currently pursuing the M.S. degree with Chongqing University of Posts and Telecommunications, Chongqing, China. His research direction is ultrafast fiber lasers.

Generation of mode-locked states of conventional solitons and bright-dark solitons in graphene mode-locked fiber laser

“…The bright and dark soliton pulses are located at different wavelengths, where the shorter band corresponds to the dark pulse and the longer band corresponds to the bright pulse, which has also been reported in Ref. [ 19 ] and will be discussed later in detail. Adjusting the PC changes the intensity and relative time position of the two kinds of pulses [ 20 ], so the bright and dark pulses can compete with each other, resulting in changes of the shape of the bright-dark soliton pairs.…”

“…Thus, in the dual-wavelength optical spectrum of the bright-dark soliton pairs, the dark solitons correspond to the shorter wavelength band, while the bright solitons correspond to the longer wavelength band. Interaction between the two wavelengths eventually generates bright-dark soliton pairs in the negative dispersion region [ 19 ].

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