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Updated: May 30, 2026
11:33
All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
Spin fluctuation effects on the conductance through a single Pd atom contact
M A Romero1, S C Gómez-Carrillo, P G Bolcatto
1Instituto de Desarrollo Tecnológico para la Industria Química (INTEC), Universidad Nacional del Litoral, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Güemes 3450 CC 91, 3000 Santa Fe, Argentina.
Summary
This study theoretically analyzes palladium single-atom contacts, explaining conductance values below quantum unity observed in Kondo regimes. The findings align with experimental trends in single-molecule transistors.
Area of Science:
- Condensed Matter Physics
- Quantum Transport
- Surface Science
Background:
- A persistent controversy exists regarding conductance values through single atoms, particularly below the quantum limit G(0) = 2e(2)/h.
- Experiments have reported conductance values near G(0)/2 at room temperature for palladium (Pd) single-atom contacts, often linked to Kondo regimes with high Kondo temperatures.
Purpose of the Study:
- To theoretically analyze the conductance of a palladium single-atom break junction.
- To investigate the Kondo regime in single-atom contacts with limited charge fluctuations.
Main Methods:
- Utilizing a realistic description of the interacting system to calculate the projected density of states.
- Employing theoretical methods to determine the characteristics of electron transport in the Pd single-atom contact.
Main Results:
- A Kondo regime was identified in the theoretical model.
- Calculated conductance values and their temperature dependence closely matched experimental observations.
Conclusions:
- The theoretical model successfully explains the experimentally observed conductance values in palladium single-atom contacts.
- The findings provide insights into the Kondo effect in single-atom junctions and its relevance to single-molecule transistors.
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