A5034705317- Solid State Laser Technologies
- Advanced Fiber Laser Technologies
- Photorefractive and Nonlinear Optics
- Photonic and Optical Devices
- Laser-Matter Interactions and Applications
- Laser Design and Applications
- Semiconductor Lasers and Optical Devices
- Photonic Crystal and Fiber Optics
- Glass properties and applications
- Spectroscopy and Laser Applications
- Laser Material Processing Techniques
- Advanced Fiber Optic Sensors
- Optical Coherence Tomography Applications
- Luminescence Properties of Advanced Materials
- Russian Literature and Bakhtin Studies
- Foot and Ankle Surgery
- Optical Network Technologies
- Orthopedic Surgery and Rehabilitation
- Optical Systems and Laser Technology
- Tendon Structure and Treatment
- Photonic Crystals and Applications
- Neurobiology and Insect Physiology Research
- Archaeology and Historical Studies
- Phase-change materials and chalcogenides
- Philosophy, Ethics, and Existentialism
University of Portsmouth
2024
University of Leicester
2022
University of Southampton
2011-2020
Bangor University
2017
California Institute of Technology
2016
Fraunhofer USA Center Mid-Atlantic CMA
2015
University of Montana
2015
Center for Environmental Health
2015
Northern Hospital
2013
Colorado State University
2009
<h3>BACKGROUND</h3> Existing murine models of asthma lack many the inflammatory and epithelial changes that are typical human disease. Moreover, these frequently complicated by allergic alveolitis. <h3>METHODS</h3> High IgE responder BALB/c mice were systemically sensitised to ovalbumin chronically challenged with low particle mass concentrations aerosolised ovalbumin. Titres anti-ovalbumin in serum measured at two weekly intervals enzyme immunoassay, accumulation cells histopathological...
1. Bakhtin in the sober light of day (introduction to revised edition) - Ken Hirschkop 2. 'Everything else depends on how this business turns out.': defence Mikhail Bakhtin's dissertation as real event, high drama, and academic comedy Nikolai Pan'kov 3. Not novel: Bakhtin, poetry, truth, God Graham Pechey 4. From phenomenology dialogue: Max Scheler's phenomenological tradition development from 'Towards a philosophy act' his study Dostoevsky Brian Poole 5. reader- David Shepherd 6. Dialogic...
Efficient repetitive passive Q switching of a cladding-pumped Er–Yb fiber laser has been demonstrated by use an external-cavity configuration containing Co2+:ZnS crystal as saturable absorber. Energies much 60 µJ in pulses durations short 3.5 ns (FWHM), corresponding to peak power >10 kW, have generated, and the maximum slope efficiency with respect absorbed pump was 13%. Using bulk diffraction grating Littrow provide wavelength-selective feedback, we tuned passively Q-switched over 31 nm...
We report on the investigation of upconversion in Nd:YAG and its implications for intensely pumped devices. Analysis lifetime measurements performance a 1 at.% Nd-doped YAG amplifier give an Auger rate 7/spl times/10/sup 3/ s/sup -1/. This is significantly smaller than previously reported, but modeling devices with high-inversion densities shows that even this can still seriously degrade small-signal gain increase thermal load. The variation cross-relaxation rates doping level also...
We demonstrate broadband supercontinuum generation (SCG) in a dispersion-engineered silicon-germanium waveguide. The 3 cm long waveguide is pumped by femtosecond pulses at 2.4 μm, and the generated extends from 1.45 to 2.79 μm (at -30 dB point). broadening mainly driven of dispersive wave 1.5-1.8 region soliton fission. SCG was modeled numerically, excellent agreement with experimental results obtained.
We demonstrate passively mode-locked Yb 3+ -doped glass waveguide lasers in a quasi-monolithic configuration with maximum pulse repetition frequency up to 15.2 GHz.A semiconductor saturable absorber mirror (SESAM) is used achieve stable mode-locking around 1050 nm durations as short 811 fs and an average power 27 mW.Different samples are also employed deliver pulses rates of 4.9 GHz, 10.4 GHz 12 32 mW, 60 mW 45 respectively.The group velocity dispersion control the cavity provided by...
The advantages and potential hazards of using a planar waveguide as the host in high-power diode-pumped laser system are described. techniques discussed include use proximity-coupled diodes, double-clad waveguides, unstable resonators, tapers, integrated passive Q switches. Laser devices described based on Yb3+-, Nd3+-, Tm3+-doped YAG, monolithic highly compact lasers with outputs greater than 10 W demonstrated. prospects for scaling to 100 level further integration added functionality discussed.
We report 1.064-μm laser operation of an epitaxially grown Nd:YAG planar waveguide with thresholds as low ~0.7 mW when high-reflectivity mirrors are used. The output is single mode and, a 83% reflectivity coupler used, has diode pumped slope efficiency ~40%. Output powers in excess 60 have been obtained pumping Rhodamine 6G dye laser.
We report the first operation of an ion-implanted dielectric waveguide laser. Details Nd: YAG structure, spectroscopic properties, and laser performance are given.
We present a novel, compact and power scalable Ho:YAG laser based on intracavity side-pumping by high-power Tm:YLF slab laser. 14 W of continuous wave output is obtained at 2.09 microm in the current experiments, with clear prospect reaching 100 regime scaled version.
We report on the first demonstration of a passively mode-locked, diode-pumped, monolithic Yb:glass channel waveguide laser that incorporates semiconductor saturable absorber mirror. Stable and self-starting mode-locking is achieved in Fabry–Perot cavity configuration producing pulse repetition rate up to 4.9 GHz. The shortest duration 740 fs generated with 30 mW average output power at center wavelength 1058 nm. A maximum 81 produced during corresponding 800 fs.
We report a high-average-power mid-infrared picosecond (ps) optical parametric oscillator (OPO) based on orientation-patterned gallium arsenide (OP-GaAs), with wide wavelength tunability. The OP-GaAs OPO is synchronously pumped by thulium-doped-fiber (TDF) master power amplifier (MOPA), seeded gain-switched laser diode. At pump of 35.3 W and repetition rate 100 MHz, maximum total average output 9.7 (signal 5.7 (0.60 kW peak power), idler 4.0 (0.42 power)) obtained at signal wavelengths 3093...
We report the laser operation of a thin-film waveguide structure grown by pulsed deposition technique. A 2.7-μm-thick crystalline film neodymium doped Gd3Ga5O12 (Nd:GGG) lases at wavelength centered 1.06 μm when pumped Ti:sapphire 808 nm.
Laser oscillation in an ion-implanted planar Nd:MgO:LiNbO(3) waveguide is demonstrated for the first time to our knowledge. Details of structure, spectroscopic properties, photorefractive effects, and laser performance are given. A simple calculation absorbed power threshold gives ~8 mW, fair agreement with experimental value ~17 mW.
We report what we believe to be the first planar-technology waveguide laser in 2-μm region. Laser operation of 3H4 3H6 transition Tm3+ ions a lead germanate glass host has been observed an ion-implanted planar waveguide.
We report laser action in a Ti-diffused LiNbO3 waveguide doped with trivalent Yb ions by thermal indiffusion. Lasing was observed at 1008, 1030, and 1060 nm thresholds as low 15-mW launched pump power. reduced photorefractivity, which initially permitted only intermittent lasing, annealing the sample wet O2. The annealed lased continuously cavity formed high-reflectivity mirrors; however, 7% output coupler power exhibited instabilities. greatest value of under these conditions consistent...
We theoretically investigated the effect of spatial distribution active-ion concentration in multimode step-index waveguides on transverse-mode selection for continuous-wave laser operation. found that uniform doping a central portion as much 60% full waveguide core width is highly effective fundamental-mode operation, even under saturated, high-power conditions. Profiling dopant to match particular mode desired was also be effective, especially if it saturated inversion profile matched shape mode.
The first channel waveguide laser in Nd:YAG showing a threshold reduction of 20 times compared to planar is described. With diode pumping this ion-implanted has been operated with absorbed power thresholds as low ~500 μW good agreement theoretical expectation. Output slope efficiencies ~29% have also demonstrated.
We report operation of a high-efficiency Yb : Er single-mode fibre laser. Pumping at wavelengths 1064 nm and 820 has shown low pump power thresholds (<7 4 mW) high slope efficiencies (4.2 7.0%).