Three-component bright-dark-bright bright–dark–bright vector pulse fiber laser based on MoS2 saturable absorber

Abstract Using the saturated absorption and the high nonlinearity of the molybdenum disulfide (MoS2) saturable absorber (SA), a three-component bright–dark–bright (BDB) vector pulse fiber laser is reported. By using polarization resolved measurement and spectral filtering, it can be found that the dark pulse component and one of bright pulses components constitute the dark–bright​ pulse pair with the same polarization state. The dark–bright pair and another bright pulse are orthogonally polarized. In other words, the single BDB pulse can be also considered to be composed of the orthogonal a bright pulse and a dark–bright pulse pair. The time interval between the bright pulse and the dark–bright pulse pair remained unchanged as the pump power was increased. The experimental results clearly show the existence of a new BDB vector pulse in fiber laser.