Spin-1 two-impurity Kondo problem on a lattice
arXiv:1710.09473 · doi:10.1103/PhysRevB.97.045103
Abstract
We present an extensive study of the two-impurity Kondo problem for spin-1 adatoms on square lattice using an exact canonical transformation to map the problem onto an effective one-dimensional system that can be numerically solved using the density matrix renormalization group method. We provide a simple intuitive picture and identify the different regimes, depending on the distance between the two impurities, Kondo coupling , longitudinal anisotropy , and transverse anisotropy . In the isotropic case, two impurities on opposite(same) sublattices have a singlet(triplet) ground state. However, the energy difference between the triplet ground state and the singlet excited state is very small and we expect an effectively four-fold degenerate ground state, i.e., two decoupled impurities. For large enough the impurities are practically uncorrelated forming two independent underscreened states with the conduction electrons, a clear non-perturbative effect. When the impurities are entangled in an RKKY-like state, Kondo correlations persists and the two effects coexist: the impurities are underscreened, and the dangling spin- degrees of freedom are responsible for the inter-impurity entanglement. We analyze the effects of magnetic anisotropy in the development of quasi-classical correlations.
13 pages, 19 figures
References in corpus (44)
- The density-matrix renormalization group
- Quantum Computing in Molecular Magnets
- The numerical renormalization group method for quantum impurity systems
- Will spin-relaxation times in molecular magnets permit quantum information processing?
- Reading and Writing Single-Atom Magnets
- The role of magnetic anisotropy in the Kondo effect
- Tunable Non-local Spin Control in a Coupled Quantum Dot System
- Topological states in engineered atomic lattices
- Conformal Field Theory Approach to the 2-Impurity Kondo Problem: Comparison with Numerical Renormalization Group Results
- Giant topological insulator gap in graphene with 5d adatoms
- Electronic correlations in transport through coupled quantum dots
- Exchange interaction between single magnetic adatoms
- Control of single-spin magnetic anisotropy by exchange coupling
- Two-Impurity Kondo Effect in Double-Quantum-Dot Systems - Effect of Interdot Kinetic Exchange Coupling
- RKKY and magnetic field interactions in coupled Kondo quantum dots
- Quantum criticality in a double quantum-dot system
- Properties of anisotropic magnetic impurities on surfaces
- Interplay between Kondo effect and Ruderman-Kittel-Kasuya-Yosida interaction
- Regular and Singular Fermi Liquid fixed points in quantum impurity models
- Quantum phase transition in quantum dot trimers
- Kondo effect in coupled quantum dots: a Non-crossing approximation study
- Singular Dynamics of Underscreened Magnetic Impurity Models
- Kondo screening in a magnetically frustrated nanostructure: Exact results on a stable, non-Fermi-liquid phase
- Spin decoherence of magnetic atoms on surfaces
- Two-Site Kondo Effect in Atomic Chains
- Non Fermi Liquid behavior in the under-screened Kondo model
- Magnetic properties of single atoms of Fe and Co on Ir(111) and Pt(111)
- Ferromagnetic Kondo effect in a triple quantum dot system
- Kondo versus indirect exchange: the role of the lattice and the actual range of RKKY interactions in real materials
- Van Hove singularities in the paramagnetic phase of the Hubbard model: a DMFT study
- Competition between Kondo effect and RKKY physics in graphene magnetism
- Suppression of Kondo screening by the Dicke effect in multiple quantum dots
- Lanczos transformation for quantum impurity problems in d-dimensional lattices: application to graphene nanoribbons
- Unveiling the internal entanglement structure of the Kondo singlet
- Common non-Fermi liquid phases in quantum impurity physics
- Coherence scale of coupled Anderson impurities
- Multiple magnetic impurities on surfaces: Scattering and quasiparticle interference
- Competition between Kondo screening and indirect magnetic exchange in a quantum box
- Screening mechanisms in magnetic nanostructures
- Magnetic adatoms as memory bits: A quantum master equation analysis
- Spatial structure of correlations around a quantum impurity at the edge of a two-dimensional topological insulator
- Effect of spin-orbit interaction on a magnetic impurity in the vicinity of a surface
- Spin-Orbit-Induced Kondo Size Effect in Thin Films with 5/2-spin Impurities
- Non-perturbative effects and indirect exchange interaction between quantum impurities on metallic (111) surfaces