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Showing 1 to 11 of 11 for “"WKB approximation"”.
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Band-to-band tunneling in silicon diodes and tunnel transistors
… analysis based on the Wentzel-Kramers-Brillouin (WKB) approximation for tunneling probability combined with an uncoupled full-band Poisson equation solver and the calculated band structure changes is developed to model the experimental results. Reasonable agreement between experimental data and …
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Effect of temperature on tunneling and quantum efficiency in cigs solar cells
Utilizing the two-band approximation and Wentzel-Kramers-B ri l l oui n (WKB) approximation, by including the temperature-dependent effective masses and nonparabolicity effects, an investigation of the temperature dependent band-to-band tunneling process is discussed. In comparison with the …
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An Investigation of Full-Wave Effects on Lower-Hybrid Wave Propagation, Absorption, and Current Drive
… of this discrepancy is the breakdown of the WKB approximation raytracing is based upon and "full-wave" effects such as diffraction and interference which raytracing cannot resolve. However, this claim has never been thoroughly investigated. In this work, we replace the raytracing model for …
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Gate leakage variability in nano-CMOS transistors
… the gate dielectric, by means of an improved WKB approximation. A study of a 25 nm square gate n-type MOSFET demonstrates that combined effect of discrete random dopants and oxide thickness variation lead to starndard deviation of up to 50% (10%) of the mean gate leakage current in …
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Acoustic scattering by discontinuities in waveguides
… of the cross-modes, which must be described by a WKB approximation. The pressure field we so obtain includes older results. The new terms account for the cutoff cross-modes of the variable waveguide, which play a central role in extending the dynamic range of the theory.
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Understanding and utilizing waveguide invariant range-frequency striations in ocean acoustic waveguides
… for the waveguide invariant is derived using WKB approximation along with a normal mode description of the acoustic field in a range-independent waveguide. This formula is applicable to waveguides with arbitrary SSPs, and reveals precisely how the SSP and the seafloor reflection coefficient …
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Understanding and utilizing waveguide invariant range-frequency striations in ocean acoustic waveguides
… for the waveguide invariant is derived using WKB approximation along with a normal mode description of the acoustic field in a rangeindependent waveguide. This formula is applicable to waveguides with arbitrary SSPs, and reveals precisely how the SSP and the seafloor reflection coefficient …
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New effective theories of gravitation and their phenomenological consequences
… a nonsymmetric connection at first order in the WKB approximation. Afterwards, we use this result in a particular black-hole solution of Poincaré Gauge gravity, showing that measurable differences between the trajectories of a fermion and a boson can be observed. Motivated by this fact, we …
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A modal/WKB inversion method for determining sound speed profiles in the ocean and ocean bottom
… and mode dependent assumed values of the WKB phase integral as input data and use the WKB phase integral as a starting point for relating the index of refraction to depth. Inversion method one is restricted to monotonic or symmetric sound speed profiles and requires a measurement of the …
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Low frequency critical current noise and two level system defects in Josephson junctions
… rate. From the quantum limiting rate and the WKB approximation, we estimated that the TLS has a mass and tunneling distance product consistent with an atomic mass tunneling through crystal lattice distances. At higher temperatures TLSs have been found that obey a simple thermal activation …
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Topics in mode conversion theory and the group theoretical foundations of path integrals
… of resonant mode conversion. We describe how the WKB approximation is related to geometrical structures in phase space, and how in particular ray-tracing algorithms can be used to construct the WKB solution. We further review how to analyze the phenomena of mode conversion from the phase space …