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Showing 1 to 9 of 9 for “"phonon emission"”.
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The weakly coupled polaron
… into consideration the contribution of the multi-phonon and the phonon-cross-exchange diagrams in the self-energy, a vertex correction has been made to the lowest order diagram. The real part and the imaginary part of the self-energy are obtained. The dispersion relationship obtained by this …
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Photo-produced phonons in semiconductors
The techniques of phonon imaging are used in conjunction with photoluminescence measurements to determine the characteristics of optically generated phonon sources in Si, Ge and GaAs at 1.7K. Focused-laser excitation of a semiconductor generates phonons as a byproduct of electronic excitation. A …
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Electroabsorption effects near the direct and indirect edges of germanium
… change in the optical absorption assisted by phonon emission and absorption. The electric field dependence of the width of the oscillations in 6a above the direct energy gap agrees with the theory derived from an effective mass approximation. Analysis of the data below the gap resulted in an …
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Phonon Spectroscopy and Low-Dimensional Electron Systems
… propagation of pulses of nonequilibrium acoustic phonons and their interaction with semiconductor nanostructures are investigated. Such studies can give unique information about the properties of low-dimensional electron systems, but in order to interpret the experiments and to understand the …
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Relaxation kinetics of excitons in cuprous oxide
… distribution of the excitons is reproduced in phonon-assisted luminescence spectra. When non-equilibrium excitons are produced by a laser pulse, nanosecond-time-resolved luminescence reveals the relaxation of their kinetic energy distribution. It has been known for several years that, when the …
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Optical absorption of pure and mixed silver halides a low temperatures
… pure AgCl and AgBr is explained by the theory of phonon~assisted indirect transitions consistent with an electronic band structure with a conduction band of standard form at k = 0 and a valence band with at least one - maximum away from k == O. For pure Agel,'! the temperature dependence indicates …
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Probing the upper limits of current flow in one-dimensional carbon conductors
… at 20 (600) oC across our samples, dominated by phonons, with estimated <10% electronic contribution. The TC of GNRs is an order of magnitude lower than that of micron-sized graphene on SiO2, suggesting strong roles of edge and defect scattering, and the importance of thermal dissipation in small …
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Ultrafast exciton relaxation in quasi-one-dimensional perylene derivatives
… to ground state bleaching, stimulated emission, and excited state absorption. Both systems exhibit broad excited-state absorption features below 2.0eV, with dominant peaks between 1.8eV and 2.0eV. The monomer spectra can be consistently explained by the results of quantum-chemical …
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Luminescence characteristics of single and multiple aluminum gallium arsenide-gallium arsenide quantum-well heterostructure lasers
… The first is concerned with the highest energy emission obtainable, and is related to the position of the L indirect minima in GaAs. The location of the first indirect conduction band minima (L minima) is determined by a luminescence (emission) technique and is found to be -294 meV above the r …