Using a numerically exact first-principles many-body approach, we revisit the "prototypical" Kondo case of a cobalt impurity on copper. Even though this is considered a well understood example of the Kondo effect, we reveal an unexpectedly strong dependence of the screening properties on the parametrization of the local Coulomb tensor. As a consequence, the Kondo temperature can vary by orders of magnitude depending on the complexity of the parametrization of the electron-electron interaction. Further, we challenge the established picture of a spin-$1$ moment involving two cobalt $d$-orbitals only, as orbital-mixing interaction terms boost the contribution of the remainder of the $d$-shell.
Motivated by recent STM experiments, we explore the magnetic field induced Kondo effect that takes place at symmetry protected level crossings in finite Co adatom chains. We argue that the effective two-level system realized at a level crossing acts as an extended impurity coupled to the conduction electrons of the substrate by a distribution of Kondo couplings at the sites of the chain. Using auxiliary-field quantum Monte Carlo simulations, which quantitatively reproduce the field dependence of the zero-bias signal, we show that a proper Kondo resonance is present at the sites where the effec…
We consider a spin-1/2 Heisenberg chain coupled via a Kondo interaction to two-dimensional Dirac fermions. The Kondo interaction is irrelevant at the \textit{decoupled} fixed-point, leading to the existence of a Kondo-breakdown phase and a Kondo-breakdown critical point separating such a phase from a heavy Fermi liquid. We reach this conclusion on the basis of a renormalization group analysis, large-N calculations as well as extensive auxiliary-field quantum Monte Carlo simulations. We extract quantities such as the zero-bias tunneling conductance which will be relevant to future experiments i…
We report density functional theory plus exact diagonalization of the multi-orbital Anderson impurity model calculations for the Co adatom on the top of Cu(001) surface. For the Co atom $d$-shell occupation $n_d \approx$ 8, a singlet many-body ground state and Kondo resonance are found, when the spin-orbit coupling is included in the calculations. The differential conductance is evaluated in a good agreement with the scanning tuneling microscopy measurements. The results illustrate the essential role which the spin-orbit coupling is playing in a formation of Kondo singlet for the multi-orbital…
The Kondo temperature $T_K$ of single Co adatoms on monolayers of Ag on Cu and Au(111) is determined using Scanning Tunneling Spectroscopy. $T_K$ of Co on a single monolayer of Ag on either substrate is essentially the same as that of Co on a homogenous Ag(111) crystal. This gives strong evidence that the interaction of surface Kondo impurities with the substrate is very local in nature. By comparing $T_K$ found for Co on Cu, Ag, and Au (111)-surfaces we show that the energy scale of the many-electron Kondo state is insensitive to the properties of surface states and to the energetic position …
The Kondo zero bias anomaly of Co adatoms probed by scanning tunneling microscopy is known to depend on the height of the tip above the surface, and this dependence is different on different low index Cu surfaces. On the (100) surface, the Kondo temperature first decreases then increases as the tip approaches the adatom, while on the (111) surface it is virtually unaffected. These trends are captured by combined density functional theory and numerical renormalization group (DFT+NRG) calculations. The adatoms are found to be described by an S = 1 Anderson model on both surfaces, and ab initio c…
We examine the exchange Hamiltonian for magnetic adatoms in graphene with localized inner shell states. On symmetry grounds, we predict the existence of a class of orbitals that lead to a distinct class of quantum critical points in graphene, where the Kondo temperature scales as $T_{K}\propto|J-J_{c}|^{1/3}$ near the critical coupling $J_{c}$, and the local spin is effectively screened by a \emph{super-ohmic} bath. For this class, the RKKY interaction decays spatially with a fast power law $\sim1/R^{7}$. Away from half filling, we show that the exchange coupling in graphene can be controlled …
We study theoretically the Kondo effect for a magnetic adatom on graphene using the Anderson model.Upon obtaining the Green's function of the impurity to higher order contributions in the hybridization, we calculated analytically the selfenergy in the presence of strong correlations.It is found that the Kondo resonance takes place in a narrow energy range of the impurity level around the Fermi energy which can be tuned by a gate voltage.We show that this range is linear in the Fermi energy $|μ|$ and is significantly narrower than in the case for a normal metal.The origin of this behavior is tr…
We investigate the bias dependence of the tunneling conductance between a spin-polarized (SP) scanning tunneling microscope (STM) tip and the surface conduction states of a normal metal with a Kondo adatom. Quantum interference between tip-host metal and tip-adatom-host metal conduction paths is studied in the full range of the Fano parameter $q$. The spin-polarized STM gives rise to a splitting of the Kondo peak and asymmetry in the zero-bias anomaly depending on the lateral tip-adatom distance. For increasing lateral distances, the Kondo peak-splitting shows a strong suppression and the spin…
We investigate the orbital origin of the Fano-Kondo line shapes measured in STM spectroscopy of magnetic adatoms on metal substrates. To this end we calculate the low-bias tunnel spectra of a Co adatom on the (001) and (111) Cu surfaces with our density functional theory-based ab initio transport scheme augmented by local correlations. In order to associate different $d$-orbitals with different Fano line shapes we only correlate individual $3d$-orbitals instead of the full Co $3d$-shell. We find that Kondo peaks arising in different $d$-levels indeed give rise to different Fano features in the…
The problem of three interacting Kondo impurities is solved within a numerically exact continuous time quantum Monte Carlo scheme. A suppression of the Kondo resonance by interatomic exchange interactions for different cluster geometries is investigated. It is shown that a drastic difference between the Heisenberg and Ising cases appears for antiferromagnetically coupled adatoms. The effects of magnetic frustrations in the adatom trimer are investigated, and possible connections with available experimental data are discussed.
We theoretically investigate the spin-resolved local density of states (SR-LDOS) of a spin-polarized two-dimensional electron gas in the presence of a Kondo adatom and a STM probe. Using Green function formalism and the atomic approach in the limit of infinite Coulomb correlation, it is found an analytical SR-LDOS expression in the low temperature regime of the system. This formal result is given in terms of phase shifts originated by the adatom scattering and Fano interference. The SR-LDOS is investigated as a function of the probe position and different Fano factors. Our findings provide an …
Based on the experimental observation, that only the close vicinity of a magnetic impurity at metal surfaces determines its Kondo behaviour, we introduce a simple model which explains the Kondo temperatures observed for cobalt adatoms at the (111) and (100) surfaces of Cu, Ag, and Au. Excellent agreement between the model and scanning tunneling spectroscopy (STS) experiments is demonstrated. The Kondo temperature is shown to depend on the occupation of the d-level determined by the hybridization between adatom and substrate with a minimum around single occupancy.
We theoretically investigate the thermoelectric properties of a spin-polarized two-dimensional electron gas hosting a Kondo adatom hybridized with an STM tip. Such a setup is treated within the single-impurity Anderson model in combination with the atomic approach for the Green's functions. Due to the spin dependence of the Fermi wavenumbers the electrical and thermal conductances, together with thermopower and Lorenz number reveal beating patterns as function of the STM tip position in the Kondo regime. In particular, by tuning the lateral displacement of the tip with respect to the adatom vi…
We have studied the effect of dynamical correlations on the electronic structure of single Co adatoms on graphene monolayers with a recently developed novel method for nanoscopic materials that combines density functional calculations with a fully dynamical treatment of the strongly interacting 3d-electrons. The coupling of the Co 3d-shell to the graphene substrate and hence the dynamic correlations are strongly dependent on the orbital symmetry and the system parameters (temperature, distance of the adatom from the graphene sheet, gate voltage). When the Kondo effect takes place, we find that…
We present a theoretical study for the scanning tunneling microscopy (STM) spectra of surface-supported magnetic nanostructures, incorporating strong correlation effects. As concrete examples, we study Co and Mn adatoms on the Cu(111) surface, which are expected to represent the opposite limits of the Kondo physics and local moment behavior, using a combination of density functional theory and both quantum Monte Carlo and exact diagonalization impurity solvers. We examine in detail the effects of temperature $T$, correlation strength $U$, and the impurity $d$ electron occupancy $N_d$ on the lo…
A detailed analysis of the Kondo effect of a magnetic impurity in a zigzag graphene nanoribbon is addressed. An adatom is coupled to the graphene nanoribbon via a hybridization amplitude $Γ_{imp}$ in a hollow or top site configuration. In addition, the adatom is also weakly coupled to a metallic STM tip by a hybridization function $Γ_{tip}$ that provides a Kondo screening of its magnetic moment. The entire system is described by an Anderson-like Hamiltonian whose low-temperature physics is accessed by employing the numerical renormalization group approach, which allows us to obtain the thermod…
We study the role of the onset of Shockley states, $D_s$, belonging to (111) surfaces of Cu, Ag and Au in the Kondo effect when a magnetic impurity is deposited on them. When $D_s$ approaches to the Fermi level, $E_F$, thing that can be done by compressing (stretching) the metallic sample, we found that most of the thermodynamic and dynamic properties of the impurity are affected in a non trivial way. We model the system by a generic Anderson impurity model and solve it by using the numerical renormalization group, NRG, technique. In particular, the impurity contribution to magnetic susceptibi…
We study the Kondo effect of a single magnetic adatom on the surface of graphene. It was shown that the unique linear dispersion relation near the Dirac points in graphene makes it more easy to form the local magnetic moment, which simply means that the Kondo resonance can be observed in a more wider parameter region than in the metallic host. The result indicates that the Kondo resonance indeed can form ranged from the Kondo regime, to the mixed valence, even to the empty orbital regime. While the Kondo resonance displays as a sharp peak in the first regime, it has a peak-dip structure and/or…
We consider the magnetic interaction of manganese phtalocyanine (MnPc) absorbed on Pb layers which were grown on a Si substrate. We perform an ab-initio calculation of the density of states and Kondo temperature as function of the number of Pb monolayers. Comparison to experimental data [Phys. Rev. Lett. 99, 256601 (2007)] then allows us to determine the exchange coupling constant J between the spins of the adsorbed molecules and those of the Pb host. This approach gives rise to a general and reliable method for obtaining J, by combining experimental and numerical results.
We study spin-dependent conductance in a system composed of a ferromagnetic (FM) Scanning Tunneling Microscope (STM) tip coupled to a metallic host surface with an adatom. The Kondo resonance is taken into account via the Doniach-Sunjic spectral function. For short lateral tip-adatom distances and due to the interplay between Kondo physics, quantum interfering effects and the ferromagnetism of the tip, a spin-splitting of the Fano-Kondo line shape arises in the conductance. A strong enhancement of the Fano-Kondo profile for the majority spin component of the FM tip is observed. When the tip is…
We carefully consider the interplay between ferromagnetism and the Kondo screening effect in the conventional Kondo lattice systems at finite temperatures. Within an effective mean-field theory for small conduction electron densities, a complete phase diagram has been determined. In the ferromagnetic ordered phase, there is a characteristic temperature scale to indicate the presence of the Kondo screening effect. We further find two distinct ferromagnetic long-range ordered phases coexisting with the Kondo screening effect: spin fully polarized and partially polarized states. A continuous phas…
We investigate the effect of geometrical frustration on the competition between the Kondo coupling and the Ruderman-Kittel-Kasuya-Yosida interaction in Kondo lattice systems. By variational Monte Carlo simulations, we reveal an emergent quantum phase with partial ordering in which the frustration is relieved by forming a magnetic order on a sublattice and leaving the rest in the Kondo screening with spin-singlet formation. The role of quantum fluctuations and spin-charge interplay is elucidated.
Renormalization group theory of the Kondo effect predicts that an impurity spin is screened by a conduction electron spread over a large distance of order >.1 to 1 micron. This review has the following sections: 1. The Kondo effect and the screening cloud, 2. Non-observation of the Kondo cloud in conventional experiments, 3. Kondo effect in transmission through a quantum dot, 4. Observing the screening cloud in persistent current experiments, 5. Side-coupled quantum dot, 6. Conclusions
Low-temperature scanning tunneling spectroscopy reveals that the Kondo temperature T_K of Co atoms adsorbed on Cu/Co/Cu(100) multilayers varies between 60 K and 134 K as the Cu film thickness decreases from 20 to 5 atomic layers. The observed change of T_K is attributed to a variation of the density of states at the Fermi level ρ_F induced by quantum well states confined to the Cu film. A model calculation based on the quantum oscillations of ρ_F at the belly and the neck of the Cu Fermi surface reproduces most of the features in the measured variation of T_K.
We show that local moment screening in a Kondo lattice with d-wave superconducting conduction electrons is qualitatively different from the corresponding single Kondo impurity case. Despite the conduction-electron pseudogap, Kondo-lattice screening is stable if the gap amplitude obeys $Δ<\sqrt{\tk D}$, in contrast to the single impurity condition $Δ<\tk$ (where $\tk$ is the Kondo temperature for $Δ= 0$ and D is the bandwidth). Our theory explains the heavy electron behavior in the d-wave superconductor Nd_{2-x}Ce_{x}CuO_{4}.
We study the Kondo screening of a magnetic impurity in a two-dimensional superconductor with Rashba spin-orbit coupling (SOC). It is found that the Rashba interaction generates a novel Kondo screening channel, in which the local moment is screened by the exchange coupling with conduction electrons in different spin and orbital states. The Kondo temperature associated with this process is determined by the interplay between the Rashba SOC and superconducting energy gap. As a result, the quantum phase transition between the magnetic doublet and Kondo singlet ground states is significantly affect…
Probing Collective and Individual Kondo Screening: Multi-Stage, Multi-Channel Kondo Effects in a $C_3$-Symmetric Four-Impurity Model
Chongqing University（重庆大学）；Hangzhou Normal University（杭州师范大学）；Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所）；School of Physical Sciences, University of Chinese Academy of Sciences（中国科学院大学物理科学学院）
The magnetic coupling between single Co atoms adsorbed on a copper surface is determined by probing the Kondo resonance using low-temperature scanning tunneling spectroscopy. The Kondo resonance, which is due to magnetic correlation effects between the spin of a magnetic adatom and the conduction electrons of the substrate, is modified in a characteristic way by the coupling of the neighbouring adatom spins. Increasing the interatomic distance of a Cobalt dimer from 2.56A to 8.1A we follow the oscillatory transition from ferromagnetic to antiferromagnetic coupling. Adding a third atom to the a…
We study the Kondo screening effect generated by a single-electron transistor or quantum dot embedded in a small metallic ring. When the ring circumference $L$ becomes comparable to the fundamental length scale $ξ_K^0=\hbar \upsilon _F/T_K^0$ associated with the {\it bulk} Kondo tempe the Kondo resonance is strongly affected, depending on the total number of electrons ({\it modulo} 4) and magnetic flux threading the ring. The resulting Kondo-assisted persistent currents are also calculated in both Kondo and mixed valence regimes, and the maximum values are found in the crossover region.
A fundamental prediction of scaling theories of the Kondo effect is the screening of an impurity spin by a cloud of electrons spread out over a mesoscopic distance. This cloud has never been observed experimentally. Recently, aspects of the Kondo effect have been observed in experiments on quantum dots embedded in quantum wires. Since the length of the wire may be of order the size of the screening cloud, such systems provide an ideal opportunity to observe it. We point out that persistent current measurements in a closed ring provide a conceptually simple way of detecting this fundamental len…
A magnetic moment in a metal or in a quantum dot is, at low temperatures, screened by the conduction electrons through the mechanism of the Kondo effect. This gives rise to spin-spin correlations between the magnetic moment and the conduction electrons, which can have a substantial spatial extension. We study this phenomenon, the so-called Kondo cloud, by means of the density matrix renormalization group method for the case of the single-impurity Anderson model. We focus on the question whether the Kondo screening length, typically assumed to be proportional to the inverse Kondo temperature, c…
While standard heavy fermion metals feature a single spin-1/2 local moment per unit cell, more complicated systems with multiple distinct local moments have been synthesized as well, with Ce_3Pd_20(Si,Ge)_6 being one example. Here, we discuss the physics of a Kondo lattice model with two local-moment sublattices, coupled with different Kondo couplings to conduction electrons. The phase diagram will be strongly modified from that of the standard Kondo lattice if the characteristic screening temperatures of the distinct moments are well separated. Therefore, we investigate the interplay between …
A spin-1/2 Anderson impurity in a semiconductor quantum well with Rashba and Dresselhaus spin-orbit couplings is studied by using a variational wave function method. The local magnetic moment is found to be quenched at low temperatures. The spin-spin correlations of the impurity and the conduction electron density show anisotropy in both spatial and spin spaces, which interpolates the Kondo spin screenings of a conventional metal and of a surface of three-dimensional topological insulators.
This is an addendum to our previous work cond-mat/9705048 (published in Europhysics Letters 41, 213 (1998)), clarifying the construction of the two-particle scattering matrices used for studying the magnetic impurity behavior in a multichannel correlated host.
Motivated by recent Hall-effect experiment in YbRh$_2$Si$_2$, we study ground state properties of a Kondo lattice model in a two-dimensional square lattice using variational Monte Carlo method. We show that there are two types of phase transition, antiferromagnetic transition and topological one (Fermi surface reconstruction). In a wide region of parameters, these two transitions occur simultaneously without the breakdown of Kondo screening, accompanied by a discontinuous change of the Hall coefficient. This result is consistent with the experiment and gives a novel theoretical picture for the…
We study the Kondo model --a magnetic impurity coupled to a one dimensional wire via exchange coupling-- by using Wilson's numerical renormalization group (NRG) technique. By applying an approach similar to which was used to compute the two impurity problem we managed to improve the bad spatial resolution of the numerical renormalization group method. In this way we have calculated the impurity spin - conduction electron spin correlation function which is a measure of the Kondo compensation cloud whose existence has been a long standing problem in solid state physics. We also present results o…
We introduce and study a simplification of the symmetric single-impurity Kondo model. In the Ising-Kondo model, host electrons scatter off a single magnetic impurity at the origin whose spin orientation is dynamically conserved. This reduces the problem to potential scattering of spinless fermions that can be solved exactly using the equation-of-motion technique. The Ising-Kondo model provides an example for static screening. At low temperatures, the thermodynamics at finite magnetic fields resembles that of a free spin-1/2 in a reduced external field. Alternatively, the Curie law can be inter…
We investigate the paramagnetic periodic Anderson model using the dynamical mean-field theory in combination with the modified perturbation theory which interpolates between the weak and strong coupling limits. For the symmetric PAM, the ground state is always a singlet state. However, as function of the hybridization strength, a crossover from collective to local Kondo screening is found. Reducing the number of conduction electrons, the local Kondo singlets remain stable. The unpaired f-electrons dominate the physics of the system. For very low conduction electron densities, a large increase …
We show that the long distance charge density oscillations in a metal induced by a weakly coupled spin-1/2 magnetic impurity exhibiting the Kondo effect are given, at zero temperature, by a universal function F(r/xi_K) where r is the distance from the impurity and xi_K, the Kondo screening cloud size =v_F/T_K, where v_F is the Fermi velocity and T_K is the Kondo temperature. F is given by a Fourier-like transform of the T-matrix. Analytic expressions for F(r/xi_K) are derived in both limits r much less than xi_K and r much greater than xi_K and F is calculated for all r/xi_K using numerical me…
The variational cluster approach (VCA) based on the self-energy functional theory is applied to the two-dimensional symmetric periodic Anderson model at half filling. We calculate a variety of physical quantities including the staggered moments and single-particle spectra at zero temperature to show that the symmetry breaking due to antiferromagnetic ordering occurs in the strong coupling region, whereas in the weak coupling region, the Kondo insulating state without symmetry breaking is realized. The critical interaction strength is estimated. We thus demonstrate that the phase transition due…
UNi4B exhibits unusual properties and, in particular, a unique antiferromagnetic arrangement involving only 2/3 of the U sites. Based on the low temperature behavior of this compound, we propose that the remaining 1/3 U sites are nonmagnetic due to the Kondo effect. We derive a model in which the coexistence of magnetic and nonmagnetic U sites is the consequence of the competition between frustration of the crystallographic structure and instability of the 5f moments.
We discuss how the properties of a single-channel Kondo lattice model are modified by additional screening channels. Contrary to current wisdom, additional screening channels appear to constitute a relevant perturbation which destabilizes the Fermi liquid. When a heavy Fermi surface develops, it generates zero modes for Kondo singlets to fluctuate between screening channels of different symmetry, producing a divergent composite pair susceptibility. Additional screening channels couple to these divergent fluctuations, promoting an instability into a state with long-range composite order.
The Kondo effect, an eminent manifestation of many-body physics in condensed matter, is traditionally explained as exchange scattering of conduction electrons on a spinful impurity in a metal. The resulting screening of the impurity's local moment by the electron Fermi sea is characterized by a Kondo temperature $T_K$, below which the system enters a non-perturbative strongly-coupled regime. In recent years, this effect has found its realizations beyond the bulk-metal paradigm in many other itinerant-electron systems, such as quantum dots in semiconductor heterostructures and in nanomaterials,…
We present the exact Bethe Ansatz solution of a multichannel model of one- dimensional correlated electrons coupled antiferromagnetically to a magnetic impurity of arbitrary spin S. The solution reveals that interactions in the bulk make the magnetic impurity drive both spin and charge fluctuations, producing a mixed valence at the impurity site, with an associated effective spin S_eff > S in the presence of a magnetic field. The screening of the impurity spin is controlled by its size independently of the number of channels, in contrast to the multichannel Kondo effect for free electrons.
The Kondo effect in the system consisting of a magnetic adatom on the graphene is studied. By using the non-equilibrium Green function method with the slave-boson mean field approximation, the local density of state (LDOS) and the conductance are calculated. For a doped graphene, the Kondo phase is present at all time. Surprisingly, two kinds of Kondo regimes are revealed. But for the undoped graphene, the Kondo phase only exists if the adatom's energy level is beyond a critical value. The conductance is similar to the LDOS, thus, the Kondo peak in the LDOS can be observed with the scanning tu…
The frustrated magnetism on the Kondo lattice system motivates intriguing Kondo-breakdown beyond the traditional Doniach scenario. Among them, the fractionalized Fermi liquid (FL*) has drawn a particular interest by virtue of its fractionalized nature. Here, we study the phase diagram of $J_{1}$-$J_{2}$ Kondo-Heisenberg model on a honeycomb lattice at a quarter filling. Employing the slave-fermion mean-field theory with $d \pm id$ spin liquid ansatz and exact diagonalization, we discuss the emergence of partial Kondo screening in the frustrated regime with comparable $J_{1}$ and $J_{2}$, and t…
We study the system of two magnetic impurities described by a two-impurity Kondo model where only the first impurity couples directly to the conduction band, while the second impurity interacts with the first through Heisenberg exchange coupling in a "side-coupled" configuration. We consider various choices of the impurity spins (S_1<S_2, S_1=S_2, and S_1>S_2) and we contrast the regimes where the inter-impurity exchange coupling J is either lower or higher than the Kondo temperature T_K^(0) of the first impurity in the absence of the second. This model is a high-spin generalization of the two…
A system of conduction electrons can mediate an indirect magnetic exchange between magnetic impurites. The nonlocal exchange typically competes with the local Kondo screening of the impurity magnetic moments. In case of magnetic adatoms on non-magnetic surfaces this competition is expected to be affected by different confinement effects. Here we study this situation in the regime of intermediate hybridization strengths by means of real-space dynamical mean-field theory for a one-dimensional two-impurity Anderson model. Depending on the presence of a boundary and depending on the system size, a…
We demonstrate the existence of a large Kondo screening cloud in the k-channel Kondo model using both renormalization group improved perturbation theory and the large-k limit. We study position (r) dependent spin Green's functions in both static and equal time cases. The equal-time Green's function provides a natural definition of the screening cloud profile, in which the large Kondo scale appears. At large distances it consists of both a slowly varying piece and a piece which oscillates at twice the Fermi wave-vector. This function is calculated at all r in the large-k limit. Static Green's f…
We identify the precise hallmarks of the local magnetic moment formation and its Kondo screening in the frequency structure of the generalized charge susceptibility. The sharpness of our identification even pinpoints an alternative criterion to determine the Kondo temperature of strongly correlated systems on the two-particle level, which only requires calculations at the lowest Matsubara frequency. We showcase its strength by applying it to the single impurity and the periodic Anderson model as well as to the Hubbard model. Our results represent a significant progress for the general understa…
Triangular symmetry stabilizes a novel non-Fermi-liquid phase in the three-impurity Kondo model with frustrating antiferromagnetic interactions between half-integer impurity spins. The phase arises without fine-tuning of couplings, and is stable against magnetic fields and particle-hole symmetry breaking. We find a conformal field theory describing this phase, verify it using the numerical renormalization group, and extract various exact, universal low-energy properties. Signatures predicted in electrical transport may be testable in scanning tunneling microscopy or quantum-dot experiments.
Spin-resolved spectroscopic evidence for spinarons in Co adatoms
Julius-Maximilians-Universität Würzburg（维尔茨堡大学）；Würzburg-Dresden Cluster of Excellence ct.qmat（维尔茨堡-德累斯顿卓越集群 ct.qmat）；Forschungszentrum Jülich（于利希研究中心）；JARA（亚琛-于利希研究联盟）；University of Duisburg-Essen（杜伊斯堡-埃森大学）；CENIDE（北莱茵-威斯特法伦州智能材料、系统和纳米增强中心）；Wilhelm Conrad Röntgen-Center for Complex Material Systems (RCCM)（威廉·康拉德·伦琴复杂材料系统中心）
Unraveling screening mechanisms in Kondo impurities using an NRG-MPS-based method
Institute for Theoretical Physics, ETH Zurich（苏黎世联邦理工学院理论物理研究所）；Max Planck Institute for the Physics of Complex Systems（马克斯·普朗克复杂系统物理研究所）；Department of Physics, University of Konstanz（康斯坦茨大学物理系）
The competition between Kondo screening and indirect magnetic exchange is studied for a system with geometrical frustration using dynamical mean-field theory (DMFT). We systematically scan the weak- to strong-coupling regime of the periodic Anderson model on the triangular lattice for a wide range of fillings n. The magnetic phase diagram is derived using a site-dependent DMFT approach by self-consistent mapping onto three independent single-impurity models corresponding to the three correlated f orbitals in the unit cell. At half-filling, the system is a non-magnetic Kondo insulator for all c…
