Nearly exact optical beat-to-soliton train conversion based on comb-like profiled fiber emulating a polynomial dispersion decreasing profile

We show that an optical beat signal is almost exactly converted to a soliton train through the propagation along a fiber with a polynomial dispersion decreasing profile, which is numerically optimized through iterative calculation. In the experiment, we demonstrate the 160-GHz beat-to-soliton conversion with a 40-pair comb-like profiled fiber, which is designed to emulate the optimized dispersion profile. The optical beat is compressed to a 324-fs soliton train with a high peak-to-pedestal ratio of more than 21 dB, and its spectral envelope is almost completely converted into a sech² shape.