Investigation of femtosecond electronic dephasing in CdSe nanocrystals using quantum-beat-suppressed photon echoes

Journal Article · Sun Feb 14 23:00:00 EST 1993 · Physical Review Letters; (United States)

DOI:https://doi.org/10.1103/PhysRevLett.70.1014· OSTI ID:7075992

Schoenlein, R W; Mittleman, D M; Shiang, J J; Alivisatos, A P; Shank, C V ^[1]

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1. Lawrence Berkeley Laboratory, 1 Cyclotron Road, MS 70-193A, Berkeley, California 94720 (United States) Department of Physics, University of California, Berkeley, California 94720 (United States) Department of Chemistry, University of California, Berkeley, California 94720 (United States)

We report the first direct measurements of femtosecond electronic dephasing in CdSe nanocrystals using three-pulse photon echoes and a novel mode-suppression technique. We are able to separate the dynamics of the coherently excited LO phonons from the underlying electron-hole dephasing by suppressing the quantum beats. The homogeneous linewidth of these materials at 15 K results from electronic dephasing in [similar to]85 fs, approximately half of which is due to acoustic phonon modes. Contributions from acoustic phonons dominate the homogeneous linewidth at room temperature.

• DOE Contract Number: AC03-76SF00098
• OSTI ID: 7075992
• Journal Information: Physical Review Letters; (United States), Journal Name: Physical Review Letters; (United States) Vol. 70:7; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360606* -- Other Materials-- Physical Properties-- (1992-)
CADMIUM COMPOUNDS
CADMIUM SELENIDES
CHALCOGENIDES
COUPLING
DYNAMICS
ELECTRON-PHONON COUPLING
ELECTRONIC STRUCTURE
LINE BROADENING
LINE WIDTHS
MECHANICS
PHOTO-INDUCED TRANSIENT SPECTROSCOPY
RELAXATION TIME
SELENIDES
SELENIUM COMPOUNDS
SPECTROSCOPY
TEMPERATURE DEPENDENCE