High coherent supercontinuum generation in nitrobenzene liquid-core photonic crystal fiber of elliptical air-hole inner ring

Abstract

A nitrobenzene liquid-core photonic crystal fiber (NLC-PCF) is proposed in this work. The eight elliptical air-holes in the innermost ring of the cladding of the fiber structure can contribute to flexibly regulating dispersion and restraining the fiber core. The appreciable dispersion is realized by adjusting the structural parameters of NLC-PCF, which is characterized by three zero-dispersion wavelengths (ZDWs), flat dispersion with the fluctuation of fewer than 40 ps·nm− 1·km− 1, and high nonlinearity as high as 5500 W− 1·km− 1. The propagation of femtosecond pulse and supercontinuum generation (SCG) in NLC-PCF is studied numerically when the pump wavelength is located in the normal and abnormal dispersion region near different ZDW through solving the generalized nonlinear Schrödinger equation (GNLSE) by the split-step Fourier method. The numerical results show that a highly coherent supercontinuum (SC) spanning from 1.3 to 2.8 µm is obtained when the pump pulse with the center wavelength of 1910 nm, the peak power of 1000 W, and pulse width of 50 fs propagated in the 5 cm long NLC-PCF. This research can find applications in the fields of novel liquid-core PCF design and ultrashort pulse propagation.