Observation of bound soliton in mode locked fiber laser exploiting simplified nonlinear polarization rotation

We report on the observation of bound solitons in a dispersion managed fiber ring cavity. A collimated variable optical attenuator as the key component is used to enhance the interaction between the solitons. With properly adjusting the stable bound solitons can be controllably and reproducibly generated. What the amazing result is we get twenty-one solitons bound together as a system.