Generation of supercontinuum and frequency comb in a nitrobenzene-core photonic crystal fiber with all-normal dispersion profile

Abstract

In this paper, we design a nitrobenzene-core photonic crystal fiber (NC-PCF) with all-normal dispersion profile. The nonlinear coefficient of the designed NC-PCF at wavelength 1560 nm is as high as 1.43 W−1 m−1, which is 100 times larger than that of the traditional silica PCF. We investigate the influences of the pump center wavelength, pulse width, peak power, and fiber length on the supercontinuum (SC) generation. The highly coherent SC spanning from 1.0 to 2.3μm is generated when the pump pulses with the center wavelength of 1560 nm, peak power of 20 kW, and width of 120 fs are launched into the 3 cm long NC-PCF. Finally, the SC-based optical frequency comb is obtained by assuming a 50 pulse pump source at a repetition rate of 1 GHz.