Results 201 to 210 of about 103,476 (250)

Ultrafast Phase Relaxation of Excitons via Exciton-Exciton and Exciton-Electron Collisions

Physical Review Letters, 1986
The ultrafast relaxation of excitons in GaAs, coherently excited by a short optical pulse and subjected to collisions with free carriers and noncoherent excitons which are independently created by a second synchronized light pulse, is studied directly in the time domain by a probing of the excitonic phase coherence.
, Schultheis, , Kuhl, , Honold, , Tu
openaire   +2 more sources

Luminescence due to Exciton-Electron and Exciton-Exciton Collisions in GaSe

Journal of the Physical Society of Japan, 1976
Two emission bands are observed in GaSe under N2 laser excitation at 77 K and 4.2 K. The spectral-band shapes agree with the theoretical curves for exciton-electron and exciton-exciton collision processes. Stimulated emission is ascribed to the exciton-exciton collision process.
T. Ugumori, K. Masuda, S. Namba
openaire   +1 more source

Annihilation of excitons and exciton-phonon interaction

Uspekhi Fizicheskih Nauk, 1971
This article is based on a paper given by the authors at a scientific meeting of the Division of General Physics and Astronomy of the Academy of Sciences of the USSR on May 30, 1968.
E F Gross, Sergei A Permogorov, B S Razbirin   +2 more
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Universal Inverse Scaling of Exciton–Exciton Annihilation Coefficient with Exciton Lifetime

Nano Letters, 2020
Be it for essential everyday applications such as bright light-emitting devices or to achieve Bose-Einstein condensation, materials in which high densities of excitons recombine radiatively are crucially important. However, in all excitonic materials, exciton-exciton annihilation (EEA) becomes the dominant loss mechanism at high densities. Typically, a
Shiekh Zia Uddin, Eran Rabani, Ali Javey
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Excitons, or No Excitons, That Is the Question

physica status solidi (a), 2000
We study the population of excitons in GaAs/AlGaAs quantum wells in the time span between optical excitation and optical recombination. We distinguish between 1s excitons and free electrons and holes by tracing the electron–hole exchange energy and thereby the overlap of electron and hole.
M. Oestreich, D. Hägele, J. Hübner, W.W. Rühle   +3 more
openaire   +1 more source

Exciton-exciton annihilation in TbPO4

Solid State Communications, 1976
Abstract A pulsed tuneable dye laser has been used to create high densities of excitons in TbPO 4 by resonant optical pumping into the 5 D 4 Manifold. Non-exponential decay of the fluorescent radiation from 5 D 4 is ascribed to exciton-exciton annihilation whose rate γ n , is proportional to the exciton density n , with γ = 5 × 10 -15 cm
P.C. Diggle, K.A. Gehring, R.M. Macfarlane   +2 more
openaire   +1 more source

Kinetic theory of exciton–exciton annihilation

The Journal of Chemical Physics, 2014
Weakly excited states of dye aggregates and supramolecular complexes can be characterized by single or two exciton states. Stronger excitation results in the presence of multiple excited molecules, and complex processes of internal energy transfer dynamics take place.
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Exciton and excitonic polaron in C60

Synthetic Metals, 1995
Abstract Exciton and excitonic polaron states in C 60 molecule are studied theoretically by the tight-binding model and the extended Hubbard interaction. We find that the exciting energies of the lowest singlet and triplet excitons depend sensitively upon the electron correlation.
Q.F. Huang, R.T. Fu, R.L. Fu, H.J. Ye, Thomas F. George, X. Sun   +5 more
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Influence of the phonon‐exciton interaction on exciton‐exciton quantum correlation in semiconductor microcavities

physica status solidi c, 2006
AbstractWe present an extension of the previous descriptions based on the Dynamics Controlled Truncation Scheme of light‐matter interaction beyond mean‐field, including the microscopic description of the exciton‐photon interaction. This enables the microscopic analysis of the influence of decoherence and noise on the polariton quantum correlations ...
PORTOLAN S, DI STEFANO O, SAVASTA, Salvatore, ROSSI F.   +3 more
openaire   +4 more sources

Dephasing kinetics of a coherent exciton polarization by exciton–exciton scattering

Journal of Luminescence, 2000
Abstract A system of excitons interacting via a two-particle interaction and with an external light field is treated within a boson approximation. Equations are derived and solved numerically including both the coherent interaction of the excitons and the incoherent x–x scattering on a microscopic level.
O.M. Schmitt, L. Bányai, H. Haug
openaire   +1 more source