We introduce a technique to decompose the scattered near field of two-dimensional arbitrary metaatoms into its multipole contributions. To this end we expand the scattered field upon plane wave illumination into cylindrical harmonics as known from Mie's theory. By relating these cylindrical harmonics to the field radiated by Cartesian multipoles, the contribution of the lowest order electric and magnetic multipoles can be identified.
View Article and Find Full Text PDFWe investigate dynamic localization in curved femtosecond (fs) laser written waveguide arrays. The light propagation inside the array is directly observed by monitoring fluorescence of color centers induced during the fs writing process. In addition to monochromatic excitation the spectral response of the arrays is investigated by launching white light supercontinuum into the arrays.
View Article and Find Full Text PDFWe study propagation of light beams in two-dimensional photonic lattices created by periodically curved waveguide arrays. We demonstrate that by designing the waveguide bending, one can control not only the strength and sign of the beam diffraction, but also to engineer the effective geometry and even dimensionality of the two-dimensional photonic lattice. We reveal that diffraction of different spectral components of polychromatic light can display completely different patterns in the same periodically modulated structure, e.
View Article and Find Full Text PDFWe report a novel micro-optical waveguide (MOW) on microactuating platform (MAP) light modulator for Q-switched all-fiber laser applications. The light modulator employs a fused biconical taper (FBT) coupler, which acts as MOW, mounted on an electromechanical system, MAP, where an axial stress over the waist of FBT coupler is precisely controlled to result in modulation of output power. The modulator was implemented in a clad pumped Yb3+-doped fiber laser cavity as a Qswitching element.
View Article and Find Full Text PDFPossibilities to produce sub-diffraction limited structures in thin metal films and bulk dielectric materials using femtosecond laser pulses are investigated. The physics of ultrashort pulse laser ablation of solids is outlined. Results on the fabrication of sub-micrometer structures in 100-200 nm chrome-coated surfaces by direct ablative writing are reported.
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