A new type of supercontinuum generation in hexagonal lattice C₆H₆-core PCF with broadband and low-power pump

Abstract

Most of the spectral bandwidths of previous publications are still limited by high input powers making them economically less than ideal. By using a benzene core (C6H6) photonic crystal fiber (PCF) as a new supercontinuum (SC) light source, it is possible to achieve a very large spectral broadening with hundreds of times lower peak power. Due to the change in the diameter of air holes in the first ring near the core, near-zero flattened dispersion, high nonlinearity and small attenuation can be achieved for spectral broadening. The structural geometries of two C6H6-PCFs are optimized to generate wide SC at low input energy. The SC spectrum produced in 1[Formula: see text]cm long of all dispersion fiber extends from a part of visible light to the near-infrared range at 1.3[Formula: see text][Formula: see text]m wavelength and a small pulse energy of 18[Formula: see text]pJ (or 450[Formula: see text]W of electrical input). The second PCF shows wide soliton-induced SC from 0.8 to 4.2[Formula: see text][Formula: see text]m with 71[Formula: see text]pJ pulse energy (or input power approximately 790[Formula: see text]W) at 1.5[Formula: see text][Formula: see text]m wavelength within a fiber of 12[Formula: see text]cm. The proposed structures have the potential to become a new class of microstructured optical fibers for low-cost, broad-spectrum SC generation.

Design and analysis of the C6H6-filled circular photonic crystal fiber with ultra-flat dispersion for broadband supercontinuum generation with peak power of 130 W and 250 W

“…The flat anomalous dispersion, effective mode area is quite small 2.868 µm 2 (highly nonlinear coefficient of 2126.103 W -1 • km -1 ) and loss as low as 97.924 dB m −1 are favorable conditions for #F 3 , pumped in anomalous dispersion regime, to enable SCG with a spectral width of up to 3.026 µm corresponding to a bandwidth of 2.467 µm at the 30 dB with very low peak power, as low as 130 W. Table 6 also shows that this fiber has a similar large spectral width [38] but a peak power about 4.1 times lower. Although its spectral width is 0.9 times that of [39], the peak power is 6.08 times lower. As for PCFs with other anomalous dispersions, SCG with this fiber both provides a larger bandwidth and uses much lower peak power.…”

“…For an all-normal dispersion fiber, the SCG bandwidth at 15 dB is 1.3 µm but the peak power is very high, up to 55 kW. When the air hole size in the first ring near the core is smaller than the others, the PCFs investigated in the works [13,38,39] show better SCG spectrum broadening [32] with much lower peak power, ranging from about 450 W to 790 W. However, the ultra-flat dispersion with low value across a wide wavelength range, which is so beneficial for SCG spectral broadening, has not yet been found.…”

Numerical Investigation of Optical Properties in Carbon Tetrachloride-Filled Photonic Crystal Fibers

“…Carbon tetrachloride has a nonlinear coefficient (n2 = 1.53×10 −19 m 2 /W) at λ = 1.064 µm [23] which is about 5 times higher than that of silica (n2 = 2.74×10 −20 m 2 /W), is a favorable factor to improve chromatic dispersion properties and increase the quality of SC spectrum. LPCFs with carbon tetrachloride will be more convenient to fabricate fibers in practice because of their lower toxicity when compared to carbon disulfide, nitrobenzene, benzene, or toluene [24,25] despite the smaller nonlinear coefficient. The coupling between liquid core fibers and typical silica fibers will be highly efficient thank the similarity between the linear refractive indices of carbon tetrachloride and fused silica [26,27].…”