Control of the spectral and coherent properties of a supercontinuum with pronounced soliton structures in the spectrum by using phase-modulated femtosecond pump pulses

摘要

It is found experimentally for the first time that the initial phase modulation of femtosecond pump pulses considerably affects the degree of coherence of the short-wavelength radiation of a supercontinuum with pronounced soliton structures in the spectrum generated in a microstructure fibre. The long-wavelength soliton radiation preserves the complete coherence upon changing the phase modulation of the pump pulse despite considerable variations of the carrier frequency of solitons. The maximum width of the supercontinuum and the maximum degree of coherence of its short-wavelength radiation are achieved for small positive values of the phase modulation parameters.