Experimental and theoretical study on the dissipative soliton energy quantization effect in the negative dispersion regime

We present experimental and simulation results on the dissipative soliton energy quantization effect in the negative dispersion regime of an all-fiber Er-doped ring laser. A fiber filter is inserted into the cavity to facilitate the energy flow out of the cavity under net negative dispersion value conditions, and a single-dissipative soliton operation with the maximum pulse energy of 0.135 nJ is achieved. The dissipative soliton splitting occurred when the pump power is increased by dual-pulse, triple-pulse, and four-pulse operations. Simulations based on the extended nonlinear Schrödinger equation have been performed to confirm the multiple-dissipative soliton generation and soliton energy quantization in a net negative dispersion mode-locked fiber laser. These experimental and simulation results will help to improve the pulse energy in the negative dispersion regime and provide a more unified theory for the understanding of the mode-locking regimes in negative dispersion lasers.