The Experts below are selected from a list of 252 Experts worldwide ranked by ideXlab platform
E. Daub - One of the best experts on this subject based on the ideXlab platform.
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injection dependence of spontaneous radiative recombination in crystalline silicon experimental verification and theoretical analysis
Applied Physics Letters, 2006Co-Authors: Pietro P. Altermatt, F. Geelhaar, Thorsten Trupke, X. Dai, A. Neisser, E. DaubAbstract:The radiative recombination coefficient B in crystalline bulk silicon is enhanced by the Coulomb Attraction between electrons and holes. This effect is weakened at high carrier densities due to screening. We measure the resulting dependence of B on the free-carrier density (i) by reinterpreting published data and (ii) with photoluminescence and photovoltaic measurements. We calculate the Coulomb enhancement by determining the electron-hole pair correlation function at zero interparticle distance, assuming a Debye interaction potential. Both bound and scattering state contributions are fully taken into account. Due to screening, B decreases with increasing free-carrier density.
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Injection dependence of spontaneous radiative recombination in c-Si: experiment, theoretical analysis, and simulation
NUSOD '05. Proceedings of the 5th International Conference on Numerical Simulation of Optoelectronic Devices 2005., 1Co-Authors: Pietro P. Altermatt, F. Geelhaar, Thorsten Trupke, X. Dai, A. Neisser, E. DaubAbstract:The radiative recombination coefficient B in crystalline bulk silicon is enhanced by the Coulomb Attraction between electrons and holes. This effect and hence B - is reduced at high carrier densities due to screening. We measure and numerically calculate B as a function of injection density, and with the gained model we simulate an experiment in order to extract the Coulomb-enhancement of Auger recombination.
Anatoly I. Burshtein - One of the best experts on this subject based on the ideXlab platform.
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Fluorescence Quenching by Reversible Charge Separation Followed by Ions Recombination and Their Separation Suppressed by Coulomb Attraction
Advances in Physical Chemistry, 2012Co-Authors: Anatoly I. Burshtein, A. B. DoktorovAbstract:The Stern-Volmer constant is specified for the luminescence quenched by reversible ionization of excited molecules. The exergonic branch of the Rehm-Weller free energy dependence of this constant is known to be a plateau determined by irreversible ionization being under diffusion control. In the endergonic region the ionization is reversible and competes with the irreversible in-cage recombination of ions and their escape from the cage. At strong Coulomb Attraction the latter phenomenon is shown to be negligible compared to the former that determines the shape and location of the descending branch of the Rehm-Weller curve. At weaker Coulomb Attraction (at higher solvent polarity), this curve turns down at larger endergonicity. The experimental data obtained in solvents of different polarities are put in order and in full accordance with present theory.
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The double-channel contact recombination and separation of geminate radical ion pairs in a Coulomb well.
The journal of physical chemistry. A, 2008Co-Authors: Anatoly I. Ivanov, Anatoly I. BurshteinAbstract:The influence of the Coulomb Attraction on photogenerated singlet radical ion pairs' separation and their geminate recombination to singlet and triplet neutral products is considered. Making use of the contact approximation and the rate or Hamiltonian description of the spin conversion, the quantum yields of recombination products and their diffusional dependence are investigated and fitted to the available experimental data. The nonmonotonous behavior of the triplet quantum yield of neutral products on both the Onsager radius and the triplet charge recombination rate constant are revealed and discussed in detail.
Sylvia Speller - One of the best experts on this subject based on the ideXlab platform.
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Size-dependent single-particle energy levels and interparticle Coulomb interactions in CdSe quantum dots measured by scanning tunneling spectroscopy
Physical Review B, 2006Co-Authors: L. Jdira, Peter Liljeroth, E. J. A. J. Stoffels, Daniel Vanmaekelbergh, Sylvia SpellerAbstract:We report on tunneling spectroscopy measurements on colloidal CdSe quantum dots of different sizes. The size-dependent energy level structure and electron-hole Coulomb Attraction in CdSe quantum dots are obtained by a combination of shell-tunneling spectroscopy and optical spectroscopy. The results are in good agreement with tight-binding calculations. The electron-electron interactions are investigated by shell-filling spectroscopy. The tunneling spectra in this regime are analyzed by solving the master equation for the electron and hole occupancy of the quantum dot.
D. M. Gianardi - One of the best experts on this subject based on the ideXlab platform.
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Optically pumped integrated absorber 3.4 μm laser with InAs-to-InGaAsSb type-II transition
Applied Physics Letters, 2001Co-Authors: Ron Kaspi, A. P. Ongstad, Charles E. Moeller, G. C. Dente, Joseph R. Chavez, Michael L. Tilton, D. M. GianardiAbstract:We report optically pumped lasing at λ∼3.4 μm from an integrated absorber structure in which the electrons confined in the InAs quantum wells recombine with holes in adjacent InGaAsSb layers to provide the gain. This type-II laser exhibits an estimated photon-to-photon conversion rate of ∼24% at 85 K. The self-consistent empirical pseudopotential method calculations suggest that Coulomb Attraction can lead to a strong enhancement in carrier overlap, and the resulting small shift in transition energy is consistent with that observed.
R A Hogg - One of the best experts on this subject based on the ideXlab platform.
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enhanced room temperature quantum dot effects in modulation doped inas gaas quantum dots
Applied Physics Letters, 2009Co-Authors: Y D Jang, Jaegyu Park, D Lee, D J Mowbray, M S Skolnick, Huiyun Liu, M Hopkinson, R A HoggAbstract:Modulation-doped InAs/GaAs quantum dots (QDs) show bright photoluminescence (PL) at 300 K, linear increase of PL intensity on excitation at 300 K and rather temperature insensitive PL intensity and carrier lifetime, in contrast to undoped QDs. Systematic analyses indicate that those advantageous behaviors come from the enhanced Coulomb Attraction due to excess carriers in doped QDs. The stronger Coulomb interaction increases the thermal activation energy, keeps more carriers in QDs, and provides enhanced QD characteristics at room temperature.
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Enhanced room-temperature quantum-dot effects in modulation-doped InAs/GaAs quantum dots
Applied Physics Letters, 2009Co-Authors: Y D Jang, Jaegyu Park, D Lee, D J Mowbray, M S Skolnick, Huiyun Liu, M Hopkinson, R A HoggAbstract:Modulation-doped InAs/GaAs quantum dots (QDs) show bright photoluminescence (PL) at 300 K, linear increase of PL intensity on excitation at 300 K and rather temperature insensitive PL intensity and carrier lifetime, in contrast to undoped QDs. Systematic analyses indicate that those advantageous behaviors come from the enhanced Coulomb Attraction due to excess carriers in doped QDs. The stronger Coulomb interaction increases the thermal activation energy, keeps more carriers in QDs, and provides enhanced QD characteristics at room temperature.
