Non-Fermi liquid behavior in transport through Co doped Au chains

Abstract

We calculate the conductance as a function of temperature $G(T)$ through Au monoatomic chains containing one Co atom as a magnetic impurity, and connected to two conducting leads with a 4-fold symmetry axis. Using the information derived from {\it ab initio} calculations, we construct an effective model $\Heff$ that hybridizes a 3d${}^7$ quadruplet at the Co site with two 3d${}^8$ triplets through the hopping of 5d${}_{xz}$ and 5d${}_{yz}$ electrons of Au. The quadruplet is split by spin anisotropy due to spin-orbit coupling. Solving $\Heff$ with the numerical renormalization group (NRG) % Wb: reverted my own change we find that at low temperatures $G(T)=a-b\sqrt{T}$ and the ground state impurity entropy is $\ln (2)/2$, a behavior similar to the two-channel Kondo model. Stretching the chain leads to a non Kondo phase, with the physics of the underscreened Kondo model at the quantum critical point.

Accepted in Physical Review Letters

References in corpus (11)

• The numerical renormalization group method for quantum impurity systems
• Mechanical Control of Spin States in Spin-1 Molecules and the Underscreened Kondo Effect
• Sum-rule Conserving Spectral Functions from the Numerical Renormalization Group
• Observation of the two-channel Kondo effect
• Quantum phase transition in a single-molecule quantum dot
• Universal Scaling in Non-equilibrium Transport Through a Single-Channel Kondo Dot
• Quantum criticality in a double quantum-dot system
• Tensor networks and the numerical renormalization group
• Correlated electron physics in multilevel quantum dots: phase transitions, transport, and experiment
• Quantum Transport Through a Stretched Spin--1 Molecule
• Interaction of CO with an Au monatomic chain at different strains: electronic structure and ballistic transport

Cited by in corpus (12)

• Kondo effect and spin quenching in high-spin molecules on metal substrates
• Fully compensated Kondo effect for a two-channel spin S=1 impurity
• Iron phthalocyanine on Au(111) is a "non-Landau" Fermi liquid
• Spectral evolution of the SU(4) Kondo effect from the single impurity to the two-dimensional lattice
• Relation between width of the zero-bias anomaly and Kondo temperaure in transport measurements through correlated quantum dots: Effect of asymmetric coupling to the leads
• A Model for Overscreened Kondo Effect in Ultracold Fermi Gas
• Non-Fermi liquid behaviour in non-equilibrium transport through Co doped Au chains connected to four-fold symmetric leads
• Qualitative breakdown of the non-crossing approximation for the symmetric one-channel Anderson impurity model at all temperatures
• Two-stage three-channel Kondo physics for an FePc molecule on the Au(111) surface
• Kondo physics in a Ni impurity embedded in O-doped Au chains
• Kondo behavior and conductance through $3d$ impurities in gold chains doped with oxygen
• Unusual Kondo physics in a Co impurity atom embedded in noble-metal chains