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Updated: Jun 3, 2026
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All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
Time-dependent screening of a point charge at a metal surface
V M Silkin1, A K Kazansky, E V Chulkov
1Departamento de Física de Materiales, Facultad de Química, Universidad del País Vasco, San Sebastián, Basque Country, Spain. waxslavs@sc.ehu.es
Summary
We studied charge density evolution on Cu(111) surfaces. Findings reveal surface plasmon excitations and acoustic surface plasmon propagation, impacting dynamical screening.
Area of Science:
- Condensed matter physics
- Surface science
- Computational materials science
Background:
- Dynamical screening is crucial for understanding electronic properties of materials.
- The Cu(111) surface exhibits unique electronic behaviors due to its surface state.
- Investigating charge density evolution provides insights into electron-electron interactions at surfaces.
Purpose of the Study:
- To investigate the space-time evolution of dynamical screening charge density at the Cu(111) surface.
- To understand the influence of confinement effects in a thin slab model.
- To analyze the role of surface band structure and plasmon excitations.
Main Methods:
- Linear response approximation applied to a thin slab model of Cu(111).
- Self-consistent evaluation of the energy-momentum-dependent response function.
- Inclusion of the realistic surface band structure of Cu(111).
Main Results:
- Observed fast, long-range charge density oscillations from surface plasmon modes.
- Identified shock wave propagation of electron-hole excitations with bulk Fermi velocity.
- Detected slower charge disturbance propagation along surfaces due to acoustic surface plasmons.
Conclusions:
- Confinement effects and surface band structure significantly influence dynamical screening.
- Surface plasmons and acoustic surface plasmons play key roles in charge density evolution.
- The energy band gap perpendicular to the surface affects screening mechanisms.
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