Bài báo khoa học

Three newly designed benzene-core photonic crystal fibers (BC-PCFs) can optimize both chromatic dispersion and attenuation characteristics simultaneously for the most efficient application to generate supercontinuum. The nonlinear characteristics of BC-PCFs with the circular lattice (CL), square lattice (SL), and hexagonal lattice (HL) are analyzed numerically to select the optimal PCF. The three optimized structures: #CBF1, #SBF2, and #HBF3 are intended for supercontinuum generation (SCG) in an all-normal dispersion regime. The obtained results demonstrated that although #HBF3 fiber has a larger effective mode area and attenuation than #CBF1, #SBF2 fibers, the dispersion curve of #HBF3 is flattest and closest to the zero-dispersion curve in the wavelength region of 0.8–2.0 µm hence it has the highest efficiency for SCG. These PCFs are capable of coherent octave-wide SCG in the 0.66–1.53 µm, 0.71–1.76 µm, and 0.71–1.82 µm wavelength ranges with low peak power of 0.45 kW and 40 fs pulses coupled to the core. Those fibers are the real objects for the sources of all-fiber supercontinuum, which can be substituted for glass core fibers because the nonlinearity of silica is lower than that of benzene. The proposed remedy can lead to new low-cost all-fiber optical systems.