Impact of piezoelectric fields on coherent zone-folded phonons in GaAs/AlAs superlattices
Autor: | Thomas Elsaesser, Felix Mahler, Michael Woerner, Klaus Reimann, Klaus Biermann, Christos Flytzanis |
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Přispěvatelé: | Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie (MBI), Nano-Optique, Laboratoire de physique de l'ENS - ENS Paris (LPENS (UMR_8023)), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Université Paris Diderot - Paris 7 (UPD7)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Université Paris Diderot - Paris 7 (UPD7) |
Rok vydání: | 2019 |
Předmět: |
Physics
Condensed matter physics Phonon Superlattice 02 engineering and technology Plasma Condensed Matter::Mesoscopic Systems and Quantum Hall Effect 021001 nanoscience & nanotechnology 01 natural sciences Piezoelectricity Condensed Matter::Materials Science Reflection (mathematics) Amplitude Condensed Matter::Superconductivity Picosecond 0103 physical sciences Condensed Matter::Strongly Correlated Electrons [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat] 010306 general physics 0210 nano-technology ComputingMilieux_MISCELLANEOUS Excitation |
Zdroj: | Physical Review B: Condensed Matter and Materials Physics (1998-2015) Physical Review B: Condensed Matter and Materials Physics (1998-2015), American Physical Society, 2019, 100 (12), pp.121302(R). ⟨10.1103/PhysRevB.100.121302⟩ |
ISSN: | 2469-9969 2469-9950 1098-0121 1550-235X |
Popis: | The amplitude decay of folded longitudinal acoustic phonon oscillations in GaAs/AlAs superlattices grown in the [100] and [111] directions is studied as a function of carrier excitation density. Time-resolved pump-probe measurements in reflection reveal decay times on the order of several tens of picoseconds, which are independent of the excitation density for all phonons in the [100] sample and for phonons at wave vectors $q\ensuremath{\ne}0$ in the [111] sample. In contrast, the decay time increases with carrier density for the phonon at $q=0$ in the [111] sample. This phonon couples to the photoexcited electron-hole plasma via the piezoelectric interaction. Friction in the carrier plasma induces a damping of the phonon oscillations. The impact of the piezoelectric phonon-electron coupling on the amplitude decay is reduced by screening at high carrier density, resulting in longer phonon decay times. |
Databáze: | OpenAIRE |
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