Generation and dynamics of soliton and soliton molecules from a VSe2/GO-based fiber laser

Benhai Wang,Yueyue Wang,Haobin Han,Lijun Yu,Chaoqing Dai

doi:10.1515/nanoph-2021-0543

Abstract

Abstract Recently, in addition to exploring the application of new saturable absorber devices in fiber lasers, soliton dynamics has also become a focus of current research. In this article, we report an ultrashort pulse fiber laser based on VSe2/GO nanocomposite and verify the formation process of soliton and soliton molecules by the numerical simulation. The prepared VSe2/GO-based device shows excellent saturable absorption characteristics with a modulation depth of 14.3% and a saturation absorption intensity of 0.93 MW/cm2. The conventional soliton is obtained with pulse width of 573 fs, which is currently the narrowest pulse width based on VSe2-related material, and has a signal-to-noise ratio of 60.4 dB. In addition, the soliton molecules are realized based on the VSe2/GO for the first time and have a pulse interval of ∼2.2 ps. We study the soliton dynamics through numerical simulation and reveal that before the formation of the soliton, it undergoes multiple nonlinear stages, such as soliton mode-locking, soliton splitting, and soliton oscillation. Furthermore, the results of numerical simulation are agreed well with the experimental data. These results indicate that the VSe2/GO might be another promising saturable absorber material for ultrafast photonics, and deepen the understanding of soliton dynamics in ultrafast fiber lasers.

Highlights

Ultrashort pulse fiber lasers had essential applications in the fields of micro–nano manufacture, optical modulators, three-dimensional optical tweezers, and optical communication [1,2,3]
The results of numerical simulation are agreed well with the experimental data. These results indicate that the VSe2/graphene oxide (GO) might be another promising saturable absorber material for ultrafast photonics, and deepen the understanding of soliton dynamics in ultrafast fiber lasers
By adjusting the polarization controller (PC) and pump power, the soliton molecules based on VSe2/GO nanocomposite are found for the first time

Summary

Introduction

Ultrashort pulse fiber lasers had essential applications in the fields of micro–nano manufacture, optical modulators, three-dimensional optical tweezers, and optical communication [1,2,3]. Graphene has been successfully applied to the research of ultrafast fiber lasers owing to its unique 2D structure and excellent saturation absorption characteristics [9] Inspired by this reason, researchers began to explore the new 2D structural materials with easy preparation, adjustable band gap and excellent nonlinear optical properties (i.e., topological insulators, Mxene, and transition metal dichalcogenides (TMDCs)) [10,11,12,13]. By anchoring VSe2 on GO nano film, the excellent characteristics of VSe2 and GO can be used to improve the mode locking performance This has prompted more new SA materials with broadband saturable absorption and high damage threshold to be explored and studied in erbium-doped fiber laser (EDFL). The spectral characteristics of solitons obtained by the simulation are in good agreement with the experimental results These results indicate that the VSe2/GO SA device has potential application value in the field of nonlinear optics

Preparation and characterizations of SA material

Simulation results and discussion

Conclusions