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RESEARCH PRODUCT
Quantum Well States in Two-Dimensional Gold Clusters on MgO Thin Films
Hannu HäkkinenPentti FrondeliusHans-joachim FreundKaroliina HonkalaMichael WalterNiklas NiliusXiao Linsubject
Condensed Matter - Materials ScienceMaterials scienceScanning tunneling spectroscopyMaterials Science (cond-mat.mtrl-sci)FOS: Physical sciencesGeneral Physics and AstronomyElectronic structureElectronlaw.inventionQuantum dotlawPhysics::Atomic and Molecular ClustersCluster (physics)Density functional theoryAtomic physicsScanning tunneling microscopeHOMO/LUMOdescription
The electronic structure of ultra-small Au clusters on thin MgO/Ag(001) films has been analyzed by scanning tunneling spectroscopy and density functional theory. The clusters exhibit two-dimensional (2D) quantum well states, whose shapes resemble the eigen-states of a 2D electron gas confined in a parabolic potential. From the symmetries of the HOMO and LUMO of a particular cluster, its electron filling and charge state is determined. In accordance to a DFT Bader-charge analysis, aggregates containing up to twenty atoms accumulate one to four extra electrons due to a charge transfer from the MgO/Ag interface. The HOMO - LUMO gap is found to close for clusters containing between 70 and 100 atoms.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2008-11-11 | Physical Review Letters |