Passive mode-locking of a 10 W double-clad fiber laser

We report experimental observation of bound states of soliton in passively mode-locked erbium-doped double-clad fiber laser. Operating in the anomalous dispersion regime with a double-clad fiber 10 W amplifier allows generation of up to several thousands of solitons per round trip. By increasing the pumping power we pass from one bound state to several separated bound states. The bound states self-organize them leading to harmonic mode-locking of soliton crystals.