Evolution of a Symmetry Gap and Synergetic Quantum Well States in Ultrathin Ag Films on Au(111) Substrates.

Journal Article · Mon Jan 01 00:00:00 EST 2007 · European Physics Letters

DOI:https://doi.org/10.1209/0295-5075/78/57003· OSTI ID:931734

Huang, Li ^[1]; Gong, Xingao ^[2]; Gergert, E. ^[3]; Forster, F. ^[3]; Bendounan, A. ^[3]; Reinert, F. ^[3]; Zhang, Zhenyu ^[4]

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1. Georgia Institute of Technology
2. Fudan University, China
3. Universitat Wurzburg, Germany
4. ORNL

Using first-principles calculations within density functional theory, we carry out a comprehensive study of how a symmetry gap around the Fermi level develops towards its bulk value as the thickness of Ag films grown on a Au(111) substrate increases. We show that, contrary to prevailing assumptions, the symmetry gap in ultrathin Ag films can be substantially wider than the gap of the Au substrate along the [111] direction. As a result, the first and second quantum well states (QWS) are confined within the Ag films only when the film thickness reaches about 10 and 19 monolayers, respectively. We further show that, when ultrathin Au films are grown on Ag(111) slabs of comparable thicknesses, synergetic QWS spanning across the whole (Au + Ag) systems are established. These results are discussed in comparison with high-resolution photoemission measurements.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 931734
• Journal Information: European Physics Letters, Vol. 78, Issue 5; ISSN 0295-5075
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
77 NANOSCIENCE AND NANOTECHNOLOGY
FERMI LEVEL
DENSITY FUNCTIONAL METHOD
PHOTOEMISSION
QUANTUM WELLS
SUBSTRATES
SYMMETRY
THICKNESS
THIN FILMS
SILVER
GOLD