Observation of the quasi-discrete supercontinuum at optical event horizon

Abstract

Numerically study of the formation of the quasi-discrete supercontinuum (SC) with ultrashort pulse sequence in an optical analogue is reported in the paper. The quasi-discrete SC is produced by pumping an intense pulse and a probe on each side of the zero-dispersion wavelength (ZDW) in a fiber. The nonlinear reflection between them causes the emission of new frequencies and gives rise to the generation of ultrashort pulses. Isolated narrow-band sources occur via the spectra interference of the ultrashort pulses, forming the quasi-discrete SC. Ultrashort pulses with different width are generated by changing the central wavelength of probe. Besides, high energy conversion efficiency and maximum frequency shift caused by the soliton–DW interaction also can be manipulated by varying the central wavelength of probe and time delay of the input pulses. So wider supercontinuum and high intensity tunable ultrashort pulses sequence can be acquired.