Femtosecond Dynamics of Electron Localization at Interfaces
10.1126/science.279.5348.202
Crossref journal-article
American Association for the Advancement of Science (AAAS)
Science (221)
Abstract

The dynamics of two-dimensional small-polaron formation at ultrathin alkane layers on a silver(111) surface have been studied with femtosecond time- and angle-resolved two-photon photoemission spectroscopy. Optical excitation creates interfacial electrons in quasi-free states for motion parallel to the interface. These initially delocalized electrons self-trap as small polarons in a localized state within a few hundred femtoseconds. The localized electrons then decay back to the metal within picoseconds by tunneling through the adlayer potential barrier. The energy dependence of the self-trapping rate has been measured and modeled with a theory analogous to electron transfer theory. This analysis determines the inter- and intramolecular vibrational modes of the overlayer responsible for self-trapping as well as the relaxation energy of the overlayer molecular lattice. These results for a model interface contribute to the fundamental picture of electron behavior in weakly bonded solids and can lead to better understanding of carrier dynamics in many different systems, including organic light-emitting diodes.

Bibliography

Ge, N.-H., Wong, C. M., Lingle, R. L., McNeill, J. D., Gaffney, K. J., & Harris, C. B. (1998). Femtosecond Dynamics of Electron Localization at Interfaces. Science, 279(5348), 202–205.

Authors 6
  1. N.-H. Ge (first)
  2. C. M. Wong (additional)
  3. R. L. Lingle (additional)
  4. J. D. McNeill (additional)
  5. K. J. Gaffney (additional)
  6. C. B. Harris (additional)
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Dates
Type When
Created 23 years, 1 month ago (July 27, 2002, 5:37 a.m.)
Deposited 8 months, 4 weeks ago (Dec. 8, 2024, 12:47 p.m.)
Indexed 2 weeks, 4 days ago (Aug. 19, 2025, 6:54 a.m.)
Issued 27 years, 7 months ago (Jan. 9, 1998)
Published 27 years, 7 months ago (Jan. 9, 1998)
Published Print 27 years, 7 months ago (Jan. 9, 1998)
Funders 0

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@article{Ge_1998, title={Femtosecond Dynamics of Electron Localization at Interfaces}, volume={279}, ISSN={1095-9203}, url={http://dx.doi.org/10.1126/science.279.5348.202}, DOI={10.1126/science.279.5348.202}, number={5348}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={Ge, N.-H. and Wong, C. M. and Lingle, R. L. and McNeill, J. D. and Gaffney, K. J. and Harris, C. B.}, year={1998}, month=jan, pages={202–205} }