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Title: Atomic-Layer-Resolved Local Work Functions of Pb Thin Films and Their Dependence on Quantum Well States

Abstract

The thickness dependence of the local work function (LWF) and its relationship with the quantum well states (QWSs) are studied. The measured LWF shows an oscillatory behavior between adjacent layers with a period of 2 ML and, in addition, an envelope beating pattern with a period of 9 ML. Scanning tunneling spectroscopy investigations reveal that the oscillatory LWF correlates perfectly with the formation of the QWSs: the higher the occupied QWS is, the smaller the LWF is. Through the role of the LWF, this study establishes the importance of quantum size effects in thin films for surface reactions and catalysis.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
944474
DOE Contract Number:
AC36-99-GO10337
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 90; Journal Issue: 1, 2007; Related Information: Article No. 013109
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CATALYSIS; QUANTUM WELLS; SPECTROSCOPY; THICKNESS; THIN FILMS; TUNNELING; WORK FUNCTIONS; Basic Sciences

Citation Formats

Qi, Y., Ma, X., Jiang, P., Ji, S., Fu, Y., Jia, J. F., Xue, Q. K., and Zhang, S. B.. Atomic-Layer-Resolved Local Work Functions of Pb Thin Films and Their Dependence on Quantum Well States. United States: N. p., 2007. Web. doi:10.1063/1.2403926.
Qi, Y., Ma, X., Jiang, P., Ji, S., Fu, Y., Jia, J. F., Xue, Q. K., & Zhang, S. B.. Atomic-Layer-Resolved Local Work Functions of Pb Thin Films and Their Dependence on Quantum Well States. United States. doi:10.1063/1.2403926.
Qi, Y., Ma, X., Jiang, P., Ji, S., Fu, Y., Jia, J. F., Xue, Q. K., and Zhang, S. B.. Mon . "Atomic-Layer-Resolved Local Work Functions of Pb Thin Films and Their Dependence on Quantum Well States". United States. doi:10.1063/1.2403926.
@article{osti_944474,
title = {Atomic-Layer-Resolved Local Work Functions of Pb Thin Films and Their Dependence on Quantum Well States},
author = {Qi, Y. and Ma, X. and Jiang, P. and Ji, S. and Fu, Y. and Jia, J. F. and Xue, Q. K. and Zhang, S. B.},
abstractNote = {The thickness dependence of the local work function (LWF) and its relationship with the quantum well states (QWSs) are studied. The measured LWF shows an oscillatory behavior between adjacent layers with a period of 2 ML and, in addition, an envelope beating pattern with a period of 9 ML. Scanning tunneling spectroscopy investigations reveal that the oscillatory LWF correlates perfectly with the formation of the QWSs: the higher the occupied QWS is, the smaller the LWF is. Through the role of the LWF, this study establishes the importance of quantum size effects in thin films for surface reactions and catalysis.},
doi = {10.1063/1.2403926},
journal = {Applied Physics Letters},
number = 1, 2007,
volume = 90,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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