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

Cavity Optomechanics

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 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.

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

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.

Fiber grating sensors

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

Soliton dynamics can be used for compressing optical pulses to few fs durations over a wide spectral range, and can be conveniently scaled in gas-filled hollow-core fibre by suitable design of the fibre structure and choice of gas [1] , [2] . In this fashion, similar patterns of pulse propagation can be obtained at pulse energies ranging from a few tens of nJ up to the mJ-level, and for pulse durations τ 0 up to hundreds of fs. The dynamics are controlled by the soliton order N and the spectral distance of the pulse frequency ν 0 from the zero dispersion frequency ν ZD . Here we report the existence of a region in ( N , ν ZD , τ 0 )-space where soliton-effect self-compression is optimal, provided the transmission loss of the fibre is negligible. We assess the limits set by modulational instability (MI) [3] , self-focusing (SF), and photoionisation (ION) [1] and derive a new limit set by third-order dispersion (TOD). By numerical simulation (not shown) we validate these limits, observing that if they are exceeded the compression quality degrades. Furthermore, we investigate, both theoretically and experimentally, scaling to MHz-level repetition rates, when inter-pulse effects cannot be neglected.

Soliton-effect self-compression: limits and high repetition rate scaling

In my presentation I will review our recent results on hybrid chalcogenide-silica waveguides with the focus on nanotapers, band gap guidance and mid infrared super continuum generation.

Chalcogenide-silica fibers – a novel base for nanophotonic devices

Forward stimulated light scattering by GHz acoustic resonances (ARs) guided in a µm-sized photonic crystal fiber (PCF) core gives rise to two classes of scattering: forward stimulated Raman-like scattering (SRLS) between pump and Stokes waves in the same optical mode [1], and forward stimulated inter-polarization scattering (SIPS) between orthogonally polarized pump and Stokes waves [2]. Here we study for the first time the transient switching dynamics of forward SIPS, building on previous studies that were restricted to the steady-state regime [2].

Switching characteristics of forward SIPS in photonic crystal fiber

We report efficient Raman conversion of vortex modes in twisted hydrogen-filled hollow-core photonic crystal fibers. Circular birefringence provides topological protection and broadband guidance of helically-phased modes over long distances.

Philip St. J. Russell

Papers

Soliton-effect self-compression: limits and high repetition rate scaling

Chalcogenide-silica fibers – a novel base for nanophotonic devices

Switching characteristics of forward SIPS in photonic crystal fiber

Raman Frequency Conversion between Guided Vortex Modes in Twisted Gas-Filled Photonic Crystal Fibers

Photonic Crystal Fiber Microreactor for In Situ Sensing and Photocatalysis