Bài báo khoa học

This study proposed new liquid-filled photonic crystal fiber structures as a new supercontinuum source with low pumping energy. The designed fiber has square lattices on its cross-section and its core being infiltrated by carbon disulfide. We studied numerically optical properties of the square lattice fiber with the modification of its structural parameters including lattice constant (Λ) and hole diameter (d). From the simulated results, two PCF structures supporting the best broadband supercontinuum generations were selected. The first optimized fiber #F1 having lattice pitch Λ = 1.0 µm and filling factor d1/Λ = 0.7 provides an all-normal dispersion. This fiber offers the supercontinuum spectrum broadening from 860 nm to 1738 nm (resulting in a bandwidth of 878 nm) by pumping at a wavelength of 1300 nm, 80 fs pulse duration and input energy of 1.5 nJ, corresponding to the input power of 18.75 kW. The second fiber #F2 (lattice pitch Λ = 1.5 µm, filling factor d1/Λ = 0.3) exhibits mostly anomalous dispersion region. In this fiber, the octave-spanning of the supercontinuum spectrum was formed with a bandwidth of 1935 nm from 594 nm to 2529 nm for an input pulse are 1670 nm pump wavelength, 80 fs duration and energy of 0.5 nJ, corresponding to the input power of 6.25 kW. The proposed fibers are good candidates for low-cost all-fiber sources for potential application in the fields of telecommunications and mid-infrared detection.