A5085503297- Photonic Crystal and Fiber Optics
- Advanced Fiber Optic Sensors
- Advanced Fiber Laser Technologies
- Optical Network Technologies
- Semiconductor Lasers and Optical Devices
- Solid State Laser Technologies
- Photonic and Optical Devices
- Orbital Angular Momentum in Optics
- Laser Design and Applications
- melanin and skin pigmentation
- Retinal Development and Disorders
- Optical Coatings and Gratings
- Laser-Matter Interactions and Applications
- Advanced Photonic Communication Systems
- Connexins and lens biology
University of Southampton
2008-2021
The University of Western Australia
2008
A simple technique for transverse mode selection in a large-mode-area (multimode) fiber laser is described. The exploits the different spectral responses of feedback elements based on Bragg grating and volume to achieve wavelength-dependent filtering. This approach has been applied cladding-pumped thulium-doped with multimode core single-spatial-mode output beam propagation factor (M2) 1.05 at 1923 nm. Without free-running an M2 parameter 3.3. Selective excitation higher order modes also...
A powerful angle-resolved method is presented for characterizing ray-group attenuation in cylindrical multimode waveguides that can be used the design optimization of fiber-optic sensors. It supported by an in-depth theoretical model accurate yet simple describing propagation meridional and skew rays passive waveguides. In particular, transmitted power different ray groups near- far-field profiles simulated. Also, individual parameters contributing to light extracted from experimental results.
We explore the properties of a novel stimulated Raman scattering (SRS) filtering fiber for high average or peak optical power delivery applications. The geometry is based on series circularly arranged index rods embedded in leaky silica cladding. operation principle relies resonant coupling core and rod modes wavelength-dependent leaking structure. fabricated demonstrated wide transmission window SRS with extinction excess 20 dB at Stokes wavelength, excellent robustness bending, output beam...
The responsivity of optical fibers to refractive index can be enhanced using high-order skew rays compared with meridional rays. Skew have a much higher number reflections increased interaction length along the core-cladding interface, which gives rise stronger interactions external medium. Reflection/transmission-type refractometric sensors based on twin-coupled-core and multimode showed one/two orders magnitude increase in ray excitation. sensitivity for two types are ~2000%/RIU,...
Modal interference in few-moded large-core fiber amplifiers can yield output beams with good beam quality (M2∼1.2 – 1.4) giving the impression of single-mode operation despite significant higher-order mode content. The implications for high-power devices are discussed.
A multi-kilowatt high-power fibre laser with adjustable azimuthal mode output beam profile is presented for the first time. The properties, and applications in cutting welding of various metals are presented.
The high performance of fibre lasers is largely due to the outstanding characteristics fibres as an active medium. However, there a need overcome some limits at optical powers which are imposed by design. We report on design and fabrication stimulated Raman scattering (SRS) filtering for average or peak power delivery applications. geometry based series circularly arranged index rod resonators embedded in silica cladding. operation principle relies resonant coupling core modes. fabricated...
In this letter, we demonstrate a fast fiber mode converter in short piece of special passive fiber. The switching mechanism relies on selective wavelength resonance between the core and high index surrounding ring Beam at 530 kHz from Gaussian beam shape to an expanded with corresponding M <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> 1.4 3.5 is demonstrated modified industrial pulsed laser power levels excess 15 W.
A novel method for selectively exciting a single-spatial-mode (fundamental or higher-order) in high-power multi-mode fiber laser resonator is presented. Preliminary results cladding-pumped Tm-doped silica are discussed.
This article introduces the 'twisted-end termination' technique for producing high quality fibre end terminations with ultra-low feedback reflectivity. The prospects further reduction in facet reflectivity via this and implications high-power devices are also discussed.
We report on novel approach to switch the optical beam profile in a fibre laser using short piece of special passive fibre. The switching mechanism relies selective wavelength resonance between core and high index surrounding ring Beam at 530 kHz from Gaussian shape flat-top with corresponding M<sup>2</sup> 1.4 3.5 is demonstrated modified industrial pulsed laser.
We proposed and demonstrated an all-fiber broadband tunable filter, with "band-stop" characteristics using bending of a resonant coupling fiber. Unlike conventional step-index fiber bend-induced "low-pass" filtering, this novel approach we are able to retain the filter tune long wavelength edge rejected spectral band whilst short is fixed by design. The can be readily spliced integrated high-power single mode output ytterbium- or thulium-doped lasers provide efficient filtering...
Using a specially designed all-fibre mode converter we generate and deliver so-called "petal" beam with high-power output. We observe that under partial obstruction, the petal can be reconstituted through propagation.
Fibre lasers (FLs) are mainstream industrial laser sources for applications in material processing. The next digital manufacturing era requires beam shaping capabilities to provide efficacy, energy efficiency, and new functionalities advanced [1] . Recently, we presented a robust kW-class FL with an adjustable profile offering improved processing capability, as compared standard Gaussian beams [2] output can be configured from diffraction-limited into higher M 2 petal-like shaped beams....