Interplay between Kondo effect and Ruderman-Kittel-Kasuya-Yosida interaction

Abstract

The interplay between the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction and the Kondo effect is expected to provide the driving force for the emergence of many phenomena in strongly correlated electron materials. Two magnetic impurities in a metal are the smallest possible system containing all these ingredients and define a bottom up approach towards a long term understanding of concentrated / dense systems. Here we report on the experimental and theoretical investigation of iron dimers buried below a Cu(100) surface by means of low temperature scanning tunnelling spectroscopy (STS) combined with density functional theory (DFT) and numerical renormalization group (NRG) calculations. The Kondo effect, in particular the width of the Abrikosov-Suhl resonance, is strongly altered or even suppressed due to magnetic coupling between the impurities. It oscillates as function of dimer separation revealing that it is related to the RKKY interaction mediated by the conduction electrons. Simulations based on density functional theory support this concept showing the same oscillation period and trends in the coupling strength as found in the experiment.

References in corpus (11)

• The numerical renormalization group method for quantum impurity systems
• Quantum Criticality in Heavy Fermion Metals
• Mechanical Control of Spin States in Spin-1 Molecules and the Underscreened Kondo Effect
• Energy resolution and discretization artefacts in the numerical renormalization group
• Exchange interaction between single magnetic adatoms
• Long-range Kondo signature of a single magnetic impurity
• Kondo resonance narrowing in d- and f-electron systems
• Mapping Itinerant Electrons around Kondo Impurities
• Signature of Fermi surface anisotropy in point contact conductance in the presence of defects
• Conductance of a tunnel point-contact of noble metals in the presence of a single defect
• The signature of subsurface Kondo impurities in the local tunnel current

Cited by in corpus (7)

• Probing Magnetic Excitations and Correlations in Single and Coupled Spin Systems with Scanning Tunneling Spectroscopy
• Kondo versus indirect exchange: the role of the lattice and the actual range of RKKY interactions in real materials
• Quantum well states and amplified spin-dependent Friedel oscillations in thin films
• Kondo Destruction in RKKY-Coupled Kondo Lattice and Multi-Impurity Systems
• Natural Orbitals Renormalization Group Approach to the Two-Impurity Kondo Critical Point
• Chiral magnetism of magnetic adatoms generated by Rashba electrons
• Spin-1 two-impurity Kondo problem on a lattice