Designing a two-octave spanning flat-top supercontinuum source by control of nonlinear dynamics through multi-order dispersion engineering in binary multi-clad microstructured fiber

Abstract

A flat-top, coherent supercontinuum generation (SCG) spanning ∼1540 nm from the near-infrared to short-wave infrared (NIR–SWIR) band in a host lead–silicate-based binary multi-clad microstructure fiber (BMMF) is analyzed and reported. This ultra wide band (903–2443 nm) SCG with flatness <5 dB is theoretically achieved with a combination of a low input pump power source (peak power=25 kW, pulse width=75 fs) and a short fiber length (∼8 cm) by controlling the nonlinear dynamics of propagating ultrashort pulses accurately through multi-order dispersion engineering. Simulations reveal that by appropriately controlling the fourth-order dispersion coefficient, a great enhancement in the spectral flatness can be achieved when the device is operated close to the maximum dispersion wavelength in the all-normal dispersion regime.