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Coherent Phonons (coherent + phonon)

Distribution by Scientific Domains
Physics and Astronomy75%

Selected Abstracts

Coherent acoustic phonons in a thin gold film probed by femtosecond surface plasmon resonance

JOURNAL OF RAMAN SPECTROSCOPY, Issue 11 2008
Shoichi Yamaguchi
Abstract We report on coherent phonon detection in a thin gold film by a new femtosecond pump-probe surface plasmon resonance (SPR) technique. Acoustic coherent phonons are generated impulsively in the gold film on a prism, and they are detected in the time domain through the reflectivity modulation for probe pulses that satisfy the SPR condition. We observed not only the fundamental vibration of a longitudinal acoustic phonon but also the overtones up to the fourth. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Interwell exciton dispersion engineering, coherent phonons generation and optical detectionof exciton condensate

PHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 1 2004
Yu. E. Lozovik
This issue's Editor's Choice [1] discusses interwell excitons in coupled quantum wells as a candidate for observation of different phases in an exciton system, including the very interesting phenomenon of Bose condensation. The cover picture shows schematically how the generation of coherent phonons and the angular distribution of the exciton photoluminescence (PL) from the quantum well system can be controlled by the external electric and magnetic fields. The first author, Yurii E. Lozovik, is head of the Laboratory of Spectroscopy of Nanostructures at the Institute of Spectroscopy and also Professor of Physics at the Moscow Physical and Technical Institute. His main interests are electron and electron,hole systems in nanostructures, cluster physics, quantum electrodynamics in a cavity, matter in strong magnetic fields, nanotechnology, ultrafast and near field optics, and computer simulations. [source]

Interwell exciton dispersion engineering, coherent phonons generation and optical detection of exciton condensate

PHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 1 2004
Yu. E. Lozovik
Abstract We propose to use dispersion engineering of interwell excitons in coupled quantum wells with external electric and magnetic fields in order to generate coherent phonons and to detect exciton condensate. A parallel magnetic field moves the dispersion minimum of interwell excitons away from the radiative zone and thus reduces their recombination rate. Normal electric field moves an interwell excitons dispersion minimum on the energy scale. These two fields effect can be used to tune the resonance condition of the interwell excitons recombination process via an in-well excitons level, which results in acoustic phonon emission. We show, that one can change recombination rate as well as intensity and angular distribution of the interwell excitons photoluminescence in the wide range by controlling the external fields. Based on this principle we propose and theoretically evaluate a procedure to detect the condensate of interwell excitons, as well as a scheme to obtain a coherent and monochromatic phonon beam (saser). The statistics of the phonon emission from the condensate of interwell excitons is studied. Numerical estimate for GaAs/AlGaAs coupled quantum wells is provided. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Proceedings of the 11th International Conference on Phonon Scattering in Condensed Matter (Phonons2004)

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 11 2004
Alexander Kaplyanskii
The 11th International Conference on Phonon Scattering (Phonons2004) was held in St. Petersburg, Russia, 25,30 July 2004. Both theoretical and experimental results on studies in phonon physics and related phenomena were presented and discussed. Main topical areas were: Phonons in nanostructures, coherent phonons, phononic crystals and superlattices, ultrafast acoustics, solitons and nonlinear phenomena, electron,phonon interaction, phonons in glasses and disordered materials, phonon transport and imaging, quantum fluids, lattice dynamics, and Raman and neutron scattering. [source]