Photonic crystal fibers guide light by corralling it within a periodic array of microscopic air holes that run along the entire fiber length Largely through their ability to overcome the limitations of conventional fiber optics—for example, by permitting low-loss guidance of light in a hollow core—these fibers are proving to have a multitude of important technological and scientific applications spanning many disciplines The result has been a renaissance of interest in optical fibers and their uses

https://science.sciencemag.org/content/sci/299/5605/358.full.pdf

Photonic crystal fibers

A topical review of numerical and experimental studies of supercontinuum generation in photonic crystal fiber is presented over the full range of experimentally reported parameters, from the femtosecond to the continuous-wave regime. Results from numerical simulations are used to discuss the temporal and spectral characteristics of the supercontinuum, and to interpret the physics of the underlying spectral broadening processes. Particular attention is given to the case of supercontinuum generation seeded by femtosecond pulses in the anomalous group velocity dispersion regime of photonic crystal fiber, where the processes of soliton fission, stimulated Raman scattering, and dispersive wave generation are reviewed in detail. The corresponding intensity and phase stability properties of the supercontinuum spectra generated under different conditions are also discussed.

Supercontinuum generation in photonic crystal fiber

Electron and ambipolar transport in organic field-effect transistors.

The history, fabrication, theory, numerical modeling, optical properties, guidance mechanisms, and applications of photonic-crystal fibers are reviewed

Photonic-Crystal Fibers

Photonic crystal fibers are a new class of optical fibers. Their artificial crystal-like microstructure results in a number of unusual properties. They can guide light not only through a well-known total internal reflection mechanism but using also photonic bandgap effect. In this paper different properties possible to obtain in photonic crystal fibers are reviewed. Fabrication and modeling methods are also discussed.

/pdf/photonic-crystal-fibers-4c73xzh7bi.pdf

Photonic Crystal Fibers

We demonstrate photonic crystal fibers with ultra-flattened, near zero dispersion. Two micro-structured fibers showing dispersion of 0 ± 0.6 ps/nm.km from 1.24 μm-1.44 μm wavelength and 0 ± 1.2 ps/nm.km over 1 μm-1.6 μm wavelength have been measured.

Demonstration of ultra-flattened dispersion in photonic crystal fibers

Photonic crystal fibres (PCFs) offer greatly enhanced design freedom compared to standard optical fibres. For example, they allow precise control of the chromatic dispersion (CD) profile—the frequency dependence of propagation speed—over a broad wavelength range. This permits studies of nonlinear pulse propagation in previously inaccessible parameter regimes. Here we report on spectral broadening of 100-fs pulses in PCFs with anomalously flat CD profiles. Maps of the spectral and spatio-temporal behaviour as a function of power show that dramatic conversion (to both longer and shorter wavelengths) can occur in remarkably short lengths of fibre, depending on the magnitude and shape of the CD profile. Because the PCFs used are single-mode at all wavelengths, the light always emerges in a fundamental guided mode. Excellent agreement is obtained between the experimental results and numerical solutions of the nonlinear wave equation, indicating that the underlying processes can be reliably modelled. These results show how, through appropriate choice of CD, nonlinearities can be efficiently harnessed to generate laser light at new wavelengths.

Transformation and control of ultra-short pulses in dispersion-engineered photonic crystal fibres

We report the fabrication and properties of soft glass photonic crystal fibers (PCF's) for supercontinuum generation. The fibers have zero or anomalous group velocity dispersion at wavelengths around 1550 nm, and approximately an order of magnitude higher nonlinearity than attainable in comparable silica fibers. We demonstrate the generation of an ultrabroad supercontinuum spanning at least 350 nm to 2200 nm using a 1550 nm ultrafast pump source.

Extruded soft glass photonic crystal fiber for ultrabroad supercontinuum generation

An ytterbium doped core has been incorporated into a photonic crystal fibre (PCF) with anomalous group velocity dispersion at all wavelengths longer than 730 nm. Laser action is observed for the first time in such a fibre. This demonstration of lasing in PCF is a vital step towards realising the huge potential of PCF for fibre laser applications.

Yb3+-doped photonic crystal fibre laser

We describe a method of displaying one or more pages of a document on an electronic document reading device using a second, computerised electronic device, the method comprising: running a document display management program on said second electronic device; using said management program to invoke an application running on said second electronic device to open said document on said second electronic device, such that said opening of said document is hidden from said user; using an intermediary code module, in particular a printer driver for said application, coupled to said application to generate image data representing an image of a said page of said document to be displayed on said electronic document reading device; sending said image of said page to said electronic document reading device; and displaying said image of said page on said electronic document reading device.

W.H. Reeves

Papers

Demonstration of ultra-flattened dispersion in photonic crystal fibers

Transformation and control of ultra-short pulses in dispersion-engineered photonic crystal fibres

Extruded soft glass photonic crystal fiber for ultrabroad supercontinuum generation

Yb3+-doped photonic crystal fibre laser

Electronic document reading devices