Observation of the dispersion effect of SnS2 nanosheets in all-normal-dispersion Yb-doped mode-locked fiber laser

Abstract In the present study, the dispersion effect of SnS2 nanosheets was investigated by comparing two groups of data that produced by all-normal-dispersion Yb-doped mode-locked fiber laser with SnS2 nanosheets or not. Besides, the nonlinear saturable absorption characteristics of the SnS2 were investigated experimentally. The saturation intensity and modulation depth were 6.01 MW/cm2 and 8.68%, respectively. The dispersion effect of SnS2 nanosheets significantly decreased pulse width. The pulse duration was shortened to one half or one third of the original. When the pump power was 193.3 mW, the narrowest pulse width was 1.05 ns. In this study, the dispersion effect of SAs was first observed and experimentally investigated in an all-normal-dispersion laser cavity. Based on the results here, a new method can be developed to investigate passively mode-locked fiber laser and promote the practical applications of SAs in the field of ultrafast photonics.