Local spectroscopy of a Kondo impurity: Co on Au(111)

Madhavan, Vidya; Chen, W.; Jamneala, T.; Crommie, Michael F.; Wingreen, Ned S.

doi:10.1103/physrevb.64.165412

Cited by 291 publications

(350 citation statements)

References 42 publications

Supporting

Mentioning

326

Contrasting

Unclassified

Order By: Relevance

“…Investigations of individual Co atoms on Au(1 1 1) surfaces [5,45] have found a Kondo temperature for that system of $70 K. A detailed electronic structure study of charge transfer between the Co atom and the Au(1 1 1) surface combined with sophisticated manybody calculations of the Kondo correlations has successfully understood this result [46].…”

Section: The Kondo Resonance and Strong Molecule-metal Couplingmentioning

confidence: 91%

Single-molecule transistors: Electron transfer in the solid state

Natelson

Ciszek

et al. 2006

Chemical Physics

View full text Add to dashboard Cite

Single-molecule transistors (SMTs) incorporating individual small molecules are unique tools for examining the fundamental physics and chemistry of electronic transport in molecular systems at the single nanometer scale. We describe the fabrication and characterization of such devices, and the synthesis and surface attachment chemistry of novel transition metal complexes that have been incorporated into such SMTs. We present gate-modulated inelastic electron tunneling vibrational spectroscopy of single molecules, strong Kondo physics (T K $ 75 K) as evidence of excellent molecule/electrode electronic coupling, and a demonstration that covalent attachment chemistry can produce SMTs that survive repeated thermal cycling to room temperature. We conclude with a look ahead at the prospects for these nanoscale systems.

show abstract

Section: The Kondo Resonance and Strong Molecule-metal Couplingmentioning

confidence: 91%

Single-molecule transistors: Electron transfer in the solid state

Natelson

Ciszek

et al. 2006

Chemical Physics

View full text Add to dashboard Cite

show abstract

“…In this range, one typically detects a Kondo resonance for magnetic adatoms [2,12], which is due to the interaction of a spin-state at a magnetic impurity with the conducting electrons of the underlying metal. Kondo resonances have a very characteristic signature, described by a Fano function [13,14,15]:with ǫ = (eV − ǫ 0 )/Γ. In this equation, A is the amplitude coefficient, B is the background dI/dV signal, q is the Fano line shape parameter, ǫ 0 is the energy shift of the resonance from the Fermi level due to level repulsion between the d-level and the Kondo resonance, and Γ is the half width of the resonance.…”

mentioning

confidence: 99%

Creating pseudo-Kondo resonances by field-induced diffusion of atomic hydrogen

2008

View full text Add to dashboard Cite

In low temperature scanning tunneling microscopy (STM) experiments a cerium adatom on Ag(100) possesses two discrete states with significantly different apparent heights. These atomic switches also exhibit a Kondo-like feature in spectroscopy experiments. By extensive theoretical simulations we find that this behavior is due to diffusion of hydrogen from the surface onto the Ce adatom in the presence of the STM tip field. The cerium adatom possesses vibrational modes of very low energy (3-4meV) and very high efficiency (≥ 20%), which are due to the large changes of Ce-states in the presence of hydrogen. The atomic vibrations lead to a Kondo-like feature at very low bias voltages. We predict that the same low-frequency/high-efficiency modes can also be observed at lanthanum adatoms.Scanning tunneling microscopy and spectroscopy (STM/STS) are at present the main tools to analyse the behavior of single atoms and molecules at conducting surfaces. Experiments at very low temperaturestypically around 4-5K -have contributed considerably to our understanding of single atom contacts [1], Kondoresonances and their signature in the near-contact regime [2], spin-flip excitations of single atoms and atomic chains [3,4], and vibrational excitations of single molecules [5]. Recently, the changes of electronic properties or atomic configurations due to field excitations were thoroughly investigated in STM experiments [6,7,8]. The salient feature in these experiments is the ability to modify the systems by varying the position and the field-intensity of the STM tip. However, the electronic properties of atoms can also be modified by the presence of hydrogen, as e.g. the measurements of Gupta et al. showed for nominally clean Cu(111) surfaces [9]. They obtained spectroscopic data with negative differential resistance, characteristic of vibrational excitations of a molecule [10]. Hydrogen itself, which is quite ubiquitous in a low-temperature ultra-high vacuum (UHV) environment, can only rarely be resolved in STM experiments [11]. Its effect on experimental scans has so far not been studied in great detail.The aim of this Report is to demonstrate the ability of manipulating the position of atomic hydrogen at the nanometer scale by the field of an STM tip and to determine its effect in spectroscopy experiments at very low bias voltages. In this range, one typically detects a Kondo resonance for magnetic adatoms [2,12], which is due to the interaction of a spin-state at a magnetic impurity with the conducting electrons of the underlying metal. Kondo resonances have a very characteristic signature, described by a Fano function [13,14,15]:with ǫ = (eV − ǫ 0 )/Γ. In this equation, A is the amplitude coefficient, B is the background dI/dV signal, q is the Fano line shape parameter, ǫ 0 is the energy shift of the resonance from the Fermi level due to level repulsion between the d-level and the Kondo resonance, and Γ is the half width of the resonance.In recent low-temperature experiments M. Ternes [16] found that adsorption of cerium ato...

show abstract

“…In the case of a single Co impurity, the experimental dC shows only one dip, which neither diminishes its width nor transforms into a peak as the distance between tip and surface is reduced 23,36 . In order to study the differences between the single-and double-impurity cases, we have carried out a z dependence study for the single-impurity model.…”

Section: Single Impurity Casementioning

confidence: 99%

Transport properties of a two-impurity system: A theoretical approach

et al. 2013

View full text Add to dashboard Cite

A system of two interacting Cobalt atoms, at varying distances, has been studied in a recent Scanning Tunneling Microscope experiment by J. Bork et al., Nature Physics 7, 901 (2011). We propose a microscopic model that explains, for all the experimentally analyzed interatomic distances, the physics observed in these experiments. Our proposal is based on the two-impurity Anderson model, with the inclusion of a two-path geometry for charge transport. This many-body system is treated in the finite-U Slave Boson Mean Field Approximation and the Logarithmic-Discretization Embedded-Cluster Approximation. We physically characterize the different charge transport regimes of this system at various interatomic distances and show that, as in the experiments, the features observed in the transport properties depend on the presence of two impurities but also on the existence of two conducting channels for electron transport. We interpret the splitting observed in the conductance as the result of the hybridization of the two Kondo resonances associated to each impurity.

show abstract

Local spectroscopy of a Kondo impurity: Co on Au(111)

Cited by 291 publications

References 42 publications

Single-molecule transistors: Electron transfer in the solid state

Single-molecule transistors: Electron transfer in the solid state

Creating pseudo-Kondo resonances by field-induced diffusion of atomic hydrogen

Transport properties of a two-impurity system: A theoretical approach

Contact Info

Product

Resources

About