Quantum confinement in self-assembled two-dimensional nanoporous honeycomb networks at close-packed metal surfaces

Journal Article · Sat Mar 14 00:00:00 EDT 2015 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.4913244· OSTI ID:22415488

Kepčija, N.; Huang, T. -J.; Barth, J. V. ^[1]

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1. Physik-Department E20, Technische Universität München, James-Franck Straße, 85748 Garching (Germany)

Quantum confinement of a two-dimensional electron gas by supramolecular nanoporous networks is investigated using the boundary elements method based on Green’s functions for finite geometries and electron plane wave expansion for periodic systems. The “particle in a box” picture was analyzed for cases with selected symmetries that model previously reported architectures constructed from organic and metal-organic scattering centers confining surface state electrons of Ag(111) and Cu(111). First, by analyzing a series of cases with systematically defined parameters (scattering geometry, potentials, and effective broadening), we demonstrate how the scattering processes affect the properties of the confined electrons. For the features of the local density of states reported by scanning tunneling spectroscopy (STS), we disentangle the contributions of lifetime broadening and splitting of quantum well states due to coupling of neighboring quantum dots. For each system, we analyze the local electron density distribution and relate it to the corresponding band structure as calculated within the plane-wave expansion framework. Then, we address two experimental investigations, where in one case only STS data and in the other case mainly angle-resolved photoemission spectroscopy (ARPES) data were reported. In both cases, the experimental findings can be successfully simulated. Furthermore, the missing information can be complemented because our approach allows to correlate the information obtained by STS with that of ARPES. The combined analysis of several observations suggests that the scattering potentials created by the network originate primarily from the adsorbate-induced changes of the local surface dipole barrier.

• OSTI ID: 22415488
• Journal Information: Journal of Chemical Physics, Vol. 142, Issue 10; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

77 NANOSCIENCE AND NANOTECHNOLOGY
CONFINEMENT
COPPER
COUPLING
DENSITY OF STATES
ELECTRON DENSITY
ELECTRON GAS
ELECTRONS
GREEN FUNCTION
LIFETIME
ORGANOMETALLIC COMPOUNDS
PHOTOELECTRON SPECTROSCOPY
POTENTIALS
QUANTUM DOTS
QUANTUM WELLS
SILVER
SURFACES
TUNNEL EFFECT
TWO-DIMENSIONAL SYSTEMS
WAVE PROPAGATION