Philip St. J. Russell

Bio: Philip St. J. Russell is an academic researcher from Max Planck Society. The author has contributed to research in topics: Photonic-crystal fiber & Photonic crystal. The author has an hindex of 47, co-authored 356 publications receiving 16560 citations. Previous affiliations of Philip St. J. Russell include University of Southampton & University of Erlangen-Nuremberg.

Hollow-core fibre and method of manufacturing thereof

Abstract: A hollow-core fibre ( 100 ) of non-bandgap type comprises a hollow core region ( 10 ) axially extending along the hollow-core fibre ( 100 ) and having a smallest transverse core dimension (D), wherein the core region ( 10 ) is adapted for guiding a transverse fundamental core mode and transverse higher order core modes, and an inner cladding region ( 20 ) comprising an arrangement of anti-resonant elements (AREs) ( 21, 21 A, 21 B) surrounding the core region ( 10 ) along the hollow-core fibre ( 100 ), each having a smallest transverse ARE dimension (d i ) and being adapted for guiding transverse ARE modes, wherein the core region ( 10 ) and the AREs ( 21, 21 A, 21 B) are configured to provide phase matching of the higher order core modes and the ARE modes and the ARE dimension (d i ) and the core dimension (D) are selected such that a ratio of the ARE and core dimensions (d i /D) is approximated to a quotient of zeros of Bessel functions of first kind (u lm,ARE /u lm,core ), multiplied with a fitting factor in a range of 0.9 to 1.5, with m being the m-th zero of the Bessel function of first kind of order l, said zeros of the Bessel functions describing the LP lm ARE modes and LP lm higher order core modes, respectively. Furthermore, an optical device ( 200 ) including the hollow-core fibre ( 100 ) and a method of manufacturing the hollow-core fibre are described.

Selective excitation of higher order modes in hollow-core PCF via prism-coupling

Abstract: Prism-coupling through the microstructured cladding is used to selectively excite individual higher order modes in hollow-core photonic crystal fibers (PCFs). Mode selection is achieved by varying the angle between the incoming beam and the fiber axis, in order to match the axial wavevector component to that of the desired mode. The technique allows accurate measurement of the effective indices and transmission losses of modes of arbitrary order, even those with highly complex transverse field distributions that would be extremely difficult to excite by conventional endfire coupling.

40-MHz all-fiber acoustooptic frequency shifter

Abstract: We report the first demonstration of a 40 MHz four-port all-fiber frequency shifter operating at a wavelength of 1.55 /spl mu/m. The device has a high-conversion efficiency and low-drive power consumption, and is made from standard telecommunications fiber.

Direct characterisation of tuneable few-femtosecond dispersive-wave pulses in the deep UV.

Abstract: Dispersive wave emission (DWE) in gas-filled hollow-core dielectric waveguides is a promising source of tuneable coherent and broadband radiation, but so far the generation of few-femtosecond pulses using this technique has not been demonstrated. Using in-vacuum frequency-resolved optical gating, we directly characterise tuneable 3fs pulses in the deep ultraviolet generated via DWE. Through numerical simulations, we identify that the use of a pressure gradient in the waveguide is critical for the generation of short pulses.

Cavity Optomechanics

Abstract: We review the field of cavity optomechanics, which explores the interaction between electromagnetic radiation and nano- or micromechanical motion This review covers the basics of optical cavities and mechanical resonators, their mutual optomechanical interaction mediated by the radiation pressure force, the large variety of experimental systems which exhibit this interaction, optical measurements of mechanical motion, dynamical backaction amplification and cooling, nonlinear dynamics, multimode optomechanics, and proposals for future cavity quantum optomechanics experiments In addition, we describe the perspectives for fundamental quantum physics and for possible applications of optomechanical devices

Photonic crystal fibers

Abstract: 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

Fourier-transform method of fringe-pattern analysis for computer-based topography and interferometry

Abstract: A fast-Fourier-transform method of topography and interferometry is proposed. By computer processing of a noncontour type of fringe pattern, automatic discrimination is achieved between elevation and depression of the object or wave-front form, which has not been possible by the fringe-contour-generation techniques. The method has advantages over moire topography and conventional fringe-contour interferometry in both accuracy and sensitivity. Unlike fringe-scanning techniques, the method is easy to apply because it uses no moving components.

Fiber grating sensors

Abstract: We review the recent developments in the area of optical fiber grating sensors, including quasi-distributed strain sensing using Bragg gratings, systems based on chirped gratings, intragrating sensing concepts, long period-based grating sensors, fiber grating laser-based systems, and interferometric sensor systems based on grating reflectors.

Supercontinuum generation in photonic crystal fiber

Abstract: 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.