0000000000660804

AUTHOR

Luis Viña

showing 2 related works from this author

Role of excitons in double Raman resonances in GaAs quantum wells

1996

Raman scattering by longitudinal-optical phonons has been measured in GaAs-AlAs multiple quantum wells at high magnetic fields. Doubly resonant scattering processes are observed at photon energies corresponding to magneto-excitons with different principal quantum numbers for the incoming and outgoing channels. The existence of these initially forbidden scattering processes, their resonance energies, and their relative intensities are correctly reproduced by our theoretical description. The model takes into account the excitonic nature of the intermediate states, as well as scattering processes involving a nonzero in-plane phonon wave vector, which is required to allow inter-Landau level sca…

PhysicsPhonon scatteringCondensed matter physicsCondensed Matter::OtherScatteringScattering lengthCorrelated Electron Systems / High Field Magnet Laboratory (HFML)02 engineering and technologyCondensed Matter::Mesoscopic Systems and Quantum Hall Effect021001 nanoscience & nanotechnology01 natural sciencesScattering amplitudeCondensed Matter::Materials Sciencesymbols.namesakeX-ray Raman scattering0103 physical sciencesPrincipal quantum numbersymbolsScattering theoryAtomic physics010306 general physics0210 nano-technologyGeneralLiterature_REFERENCE(e.g.dictionariesencyclopediasglossaries)Raman scatteringPhysical Review B
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Preservation of quantum coherence after exciton-exciton interaction in quantum wells

2003

The dynamics of exciton-exciton interaction in quantum wells has been investigated by monitoring the time-resolved resonant secondary emission that follows excitation with linearly and circularly polarized light. Preservation of quantum beating in the cross-polarized emission demonstrates that spin relaxation can take place, for some scattering channels, without total quantum coherence loss. Interexciton electron exchange is the scattering mechanism that explains the persistence of the beating and, since it is sensitive to the fine structure of excitons, the shift by pi in the phase of the beating observed in the experiment.

PhysicsCondensed matter physicsScatteringExcitonSecondary emissionCavity quantum electrodynamicsPhotodetectionAtomic physics530 PhysikQuantumQuantum wellCoherence (physics)
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