[en] We demonstrate the blue light generated in high-Δ photonic crystal fibers (PCFs). A femtosecond Yb-doped fiber laser, operating at 1039nm, is used to pump a GeO₂-doped PCF in the largely anomalous group velocity dispersion (GVD) region. The emitted radiation covers 418.6–544.6nm with 5dB flatness. The calculated result indicates that the cross phase module (XPM) effect induced by higher-mode soliton makes a contribution to the blue component generation. (fundamental areas of phenomenology(including applications))

[en] We report supercontinuum generation extending to the blue spectral region using pulses of 1.8 ps duration at 1040 nm in GeO₂-doped core photonic crystal fibers. A spectrum in fundamental mode spanning from 415 nm to beyond 1750 nm is generated in a uniform photonic crystal fiber (PCF). A zero dispersion wavelength decreasing PCF is fabricated to optimize the parameters for deeper blue components generated by cross-phase modulation and group-velocity matching. Although the PCF is pumped at a low input power of 1.3 W in anomalous dispersion and relatively far from the zero dispersion wavelength, a flat continuum covering 406.1–671.8 nm is generated, which is of primary importance in a number of bio-photonic applications such as fluorescence imaging microscopy

[en] A new single-mode fibre (SMF) with high stimulated Brillouin scattering (SBS) threshold which is co-doped with GeO₂ and F₂ in the core is reported. To increase the SBS threshold, the acousto-optic effective area is increased by designing a transverse acoustic waveguide and adjusting the doping level of GeO₂ and F₂ while the designed fiber retains a step optical refractive index profile. The optimal design is found by numerical simulation and the optimal fiber is fabricated by a plasma-activated chemical vapor deposition (PCVD) process. It yields the threshold 6.79 dB, which is higher than the conventional single-mode fiber G.652 and 3dB higher than the Corning® SMF-28e+™ optical fiber with NexCor® technology. (fundamental areas of phenomenology (including applications))