Kondo physics in a Ni impurity embedded in O-doped Au chains

Abstract

By means of ab initio calculations we study the effect of O-doping of Au chains containing a nanocontact represented by a Ni atom as a magnetic impurity. In contrast to pure Au chains, we find that with a minimun O-doping the $5d_{xz,yz}$ states of Au are pushed up, crossing the Fermi level. We also find that for certain O configurations, the Ni atom has two holes in the degenerate $3d_{xz,yz}$ orbitals, forming a spin $S=1$ due to a large Hund interaction. The coupling between the $5d_{xz,yz}$ Au bands and the $3d_{xz,yz}$ of Ni states leads to a possible realization of a two-channel $S=1$ Kondo effect. While this kind of Kondo effect is commonly found in bulk systems, it is rarely observed in low dimensions. The estimated Kondo scale of the system lies within the present achievable experimental resolution in transport measurements. Another possible scenario for certain atomic configurations is that one of the holes resides in a $3d_{z^2}$ orbital, leading to a two-stage Kondo effect, the second one with SU(4) symmetry.

References in corpus (8)

• Kondo effect in quantum dots
• Kondo resonance narrowing in d- and f-electron systems
• Properties of anisotropic magnetic impurities on surfaces
• Conductance of a spin-1 quantum dot: the two-stage Kondo effect
• Quantum Transport Through a Stretched Spin--1 Molecule
• Efficient DFT+U calculations of ballistic electron transport: Application to Au monatomic chains with a CO impurity
• Non-Fermi liquid behaviour in non-equilibrium transport through Co doped Au chains connected to four-fold symmetric leads
• Valence fluctuations in a lattice of magnetic molecules: application to iron(II) phtalocyanine molecules on Au(111)

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• Kondo temperature when the Fermi level is near a step in the conduction density of states
• The PointGroupNRG code for numerical renormalization group calculations with discrete point-group symmetries
• Anomalous behavior of the quasi-one-dimensional quantum material Na${}_2$OsO${}_4$ at high pressure