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Title: Dynamics of very low energy photoelectrons interacting with image charge of Cs/Cu(111) surface

Abstract

We have measured the very low energy photoelectron spectra of Cs-covered Cu(111) surfaces, and determined the mechanism for the appearance of a spike structure due to the interaction of emitted electron with its image charge. At high Cs coverage of 0.10 and 0.14 monolayers (ML), the spike structure appeared at the vacuum level. No such structure was found at low coverage of 0.06 ML. The vacuum level at high coverage lies in the energy gap at the {gamma} point in the surface Brillouin zone of the Cu(111) surface, while it lies outside the energy gap at low coverage. These results confirm the validity of our proposed mechanism that the spike structure appears when the vacuum level lies in the energy gap.

Authors:
; ;  [1];  [1];  [2];  [1];  [2]
  1. RIKEN Photodynamics Research Center, Sendai 980-0845 (Japan)
  2. (Japan)
Publication Date:
OSTI Identifier:
20719834
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 72; Journal Issue: 19; Other Information: DOI: 10.1103/PhysRevB.72.195425; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ADSORPTION; BRILLOUIN ZONES; CESIUM; COPPER; ELECTRON EMISSION; ELECTRONS; ENERGY GAP; IMAGES; INTERFACES; PHOTOELECTRON SPECTROSCOPY; SURFACES

Citation Formats

Hayashi, K., Arafune, R., Ueda, S., Uehara, Y., Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577, Ushioda, S., and Japan Advanced Institute of Science and Technology, Ishikawa 923-1292. Dynamics of very low energy photoelectrons interacting with image charge of Cs/Cu(111) surface. United States: N. p., 2005. Web. doi:10.1103/PhysRevB.72.195425.
Hayashi, K., Arafune, R., Ueda, S., Uehara, Y., Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577, Ushioda, S., & Japan Advanced Institute of Science and Technology, Ishikawa 923-1292. Dynamics of very low energy photoelectrons interacting with image charge of Cs/Cu(111) surface. United States. doi:10.1103/PhysRevB.72.195425.
Hayashi, K., Arafune, R., Ueda, S., Uehara, Y., Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577, Ushioda, S., and Japan Advanced Institute of Science and Technology, Ishikawa 923-1292. Tue . "Dynamics of very low energy photoelectrons interacting with image charge of Cs/Cu(111) surface". United States. doi:10.1103/PhysRevB.72.195425.
@article{osti_20719834,
title = {Dynamics of very low energy photoelectrons interacting with image charge of Cs/Cu(111) surface},
author = {Hayashi, K. and Arafune, R. and Ueda, S. and Uehara, Y. and Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577 and Ushioda, S. and Japan Advanced Institute of Science and Technology, Ishikawa 923-1292},
abstractNote = {We have measured the very low energy photoelectron spectra of Cs-covered Cu(111) surfaces, and determined the mechanism for the appearance of a spike structure due to the interaction of emitted electron with its image charge. At high Cs coverage of 0.10 and 0.14 monolayers (ML), the spike structure appeared at the vacuum level. No such structure was found at low coverage of 0.06 ML. The vacuum level at high coverage lies in the energy gap at the {gamma} point in the surface Brillouin zone of the Cu(111) surface, while it lies outside the energy gap at low coverage. These results confirm the validity of our proposed mechanism that the spike structure appears when the vacuum level lies in the energy gap.},
doi = {10.1103/PhysRevB.72.195425},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 19,
volume = 72,
place = {United States},
year = {Tue Nov 15 00:00:00 EST 2005},
month = {Tue Nov 15 00:00:00 EST 2005}
}
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