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Showing 1 to 13 of 13 for “"Mode confinement"”.
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Characterization of a turbulence bifurcation underlying L-mode confinement transitions on Alcator C-Mod
Empirical energy confinement scalings play a crucial role in the design of tokamak fusion reactors, measuring how quickly energy is transported by turbulence from the fusion-producing core to conduction loss at the edge. Unfortunately, experiments often exhibit discontinuous changes in scaling …
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Dynamic Metasurfaces for Advanced Applications
… and finally we apply developed knowledge about mode confinement in the dielectric metasurface to a novel system utilizing phase change materials. Second, traditional metal-insulator-metal metasurfaces with advanced capabilities are developed. We utilize the electronic compatibility of the MIM …
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Towards multiple quantum well optically pumped far infrared lasers
… at high pump intensities. A rate equation model agreed well with the experimental result. A novel idea of stacking two MQW slabs face-to-face to improve the mode confinement of the laser system has been proposed. Possible errors in aligning the slabs were modelled, where the estimated …
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Acoustics and manufacture of Caribbean steelpans
… by repeated impact of the note at its centre. Mode confinement in test-pans is also investigated. ISF is used to produce miniature test-pans with test-notes that are geometrically identical to notes on full size pans. It is possible to confine modes by varying the curvature of the bowl …
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Broadband electrooptic modulators based on gallium arsenide materials
… Frequency combs, generated by Ti:Sapphire mode-locked lasers, span the optical spectrum from A=0.65pm to 1.1pm and necessitate the development of compatible modulator devices which could be based on materials in the III-V semiconductor groups for the construction of an optical arbitrary …
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Edge radial electric field studies via charge exchange recombination spectroscopy on the Alcator C-Mod Tokamak
… formation of edge transport barriers and high-confinement mode (H-mode) in tokamak plasmas. However, the self consistent evolution of the radial electric field profile (Er), pedestal shape and improvement in plasma confinement is not well understood. A better understanding of pedestal physics …
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Enhanced Rainbow Trapping in Width-graded Chirped MIM Nano-gratings for High-sensitivity Multiwavelength Bio-molecular Detection
… metal-insulator-metal (MIM) nano-gratings, mode confinement and waveguiding result in multiwavelength light localization provided conditions for adiabatic mode transformation are satisfied. Maximal field enhancement is attained by ensuring adiabatic mode transformation among the grooves …
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Evolution of radial force balance and radial transport over L-H transition
Understanding of plasma confinement modes is an essential component in development of a fusion reactor. Plasma confinement directly relates to performance of a fusion reactor in terms of energy replacement time requirements on other design parameters. Although a variety of levels of confinement …
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Development of intersubband terahertz lasers using multiple quantum well structures
… inversion, new methods for long-wavelength mode confinement, and farinfrared spectral measurement techniques are critical steps in achieving this goal. Conduction-band three-level subband systems in triple-quantum-well structures using GaAs/Alo.3Gao.7As heterostructures were proposed, …
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The development of high power, pulsed fiber laser systems and their applications
… fiber allows the efficient conversion of multimode radiation from high power, low cost, broad-stripe semiconductor laser diodes into the single-mode emission of fiber lasers. With its broad gain bandwidth and high optical conversion efficiency, Yb-doped silica fiber represents an attractive …
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Investigations towards the development of a novel multimodal fibre optic sensor for oil and gas applications.
… in the O&G industry, based on step index single mode fibres (SMF), offer limited performance, as they operate within a narrow wavelength window. A novel multimodal sensor configuration, based on photonic crystal fibre (PCF) and utilising a multiwavelength approach, is proposed for the first time …
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The Low Frequency Edge Oscillation in Alcator C-Mod and ASDEX Upgrade I-Mode
The I-Mode confinement regime in tokamaks is a promising regime for nuclear fusion reactor operation for a number of reasons. It exhibits high energy confinement (similar to H-Mode) and low particle and impurity confinement (similar to L-Mode), which allows it to reach high pressures without …
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Silicon Photonics for All-Optical Processing and High-Bandwidth-Density Interconnects
… rack level interconnects, looks into a detailed model of the optical power budget for such a link capturing both single-channel aspects as well as WDM-operation-related considerations which are unique for a microring physical characteristics. The holistic analysis for the full link captures the …