Nonlinear wavelength conversion in photonic crystal fibers with three zero dispersion points

In this theoretical study, we show that a simple endlessly single-mode photonic crystal fiber can be designed to yield, not just two, but three zero-dispersion wavelengths. The presence of a third dispersion zero creates a rich phase-matching topology, enabling enhanced control over the spectral locations of the four-wave-mixing and resonant-radiation bands emitted by solitons and short pulses. The greatly enhanced flexibility in the positioning of these bands has applications in wavelength conversion, supercontinuum generation and pair-photon sources for quantum optics

Ion-beam induced nano-sized Ag-metal clusters in glass

The formation of silver-metal clusters has been studied in ion-exchanged soda-lime glass following swift heavy ion irradiation at ISL. While the transformation into a metallic chemical form was detected with X-ray absorption spectroscopy (EXAFS) the shape and geometrical arrangement was studied both by transmission electron microscopy (TEM) and small angle X-ray scattering (SAXS). A chain-like arrangement of nanoclusters, of approximately 7 nm in diameter observed in TEM was further investigated with in situ SAXS during the subsequent annealing process. (C) 2007 Elsevier B.V. All rights reserved