Related papers: Orbital Kondo behavior from dynamical structural d…
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…
We study a quantum dot connected to the bulk by single-mode junctions at almost perfect conductance. Although the average charge $e\langle N \rangle$ of the dot is not discrete, its spin remains quantized: $s=1/2$ or $s=0$, depending…
We apply the functional renormalization group (FRG) method to calculate the conductance of a quantum dot in the Kondo regime. Starting from the exact FRG equations in Keldysh formulation for the Kondo exchange Hamiltonian in pseudo-fermion…
The properties of a local spin S=1/2 coupled to K independent wires is studied in the presence of bias voltages which drive the system out of thermal equilibrium. For K >> 1, a perturbative renormalization group approach is employed to…
We extend a perturbative, nonequilibrium renormalization group approach to multi-orbital systems and apply it for studying transport through two parallel quantum dots coupled electrostatically. In general, the conductance shows pronounced…
We study transport through two quantum dots coupled by an RKKY interaction as a function of temperature and magnetic field. By applying the Numerical Renormalization Group (NRG) method we obtain the transmission and the linear conductance.…
A spin-1/2 magnetic impurity coupled to a one-dimensional correlated electron system have been studied by applying the density renormalization group method. The Kondo temperature is substantially enhanced by strong repulsive interactions in…
The conductance through a serial double dot structure for which the inter-dot tunneling is stronger than the tunneling to the leads is studied using the numerical density matrix renormalization group method and analytic arguments. When the…
We consider electron transport through a quantum dot described by the Kondo model in the regime of large transport voltage V in the presence of a magnetic field B with max(V,B) >> T_K. The electric current I and the local magnetization M…
We consider a strongly interacting quantum dot connected to two leads held at quite different temperatures. Our aim is to study the behavior of the Kondo effect in the presence of large thermal biases. We use three different approaches,…
An analytical description of non-equilibrium phenomena in interacting quantum systems is rarely possible. Here we present one example where such a description can be achieved, namely the ferromagnetic Kondo model. In equilibrium, this model…
Entanglement of spin and orbital Kondo effect is investigated on the basis of a Kondo-type exchange model with twofold orbital degeneracy. By using Wilson's numerical renormalization-group method, we examine dynamical and thermal properties…
The optical conductivity of the double exchange and the orbital degenerate Kondo lattice Hamiltonian (orbital t-J model) are invetigated by means of finite temperature diagonalization for different doping concentrations. The temperature…
The interplay between the coupling of an interacting quantum dot to a conduction band and its connection to localized levels has been studied in a triple quantum dot arrangement. The electronic Dicke effect, resulting from quasi-resonant…
We review the mechanisms of low-temperature electron transport across a quantum dot weakly coupled to two conducting leads. Conduction in this case is controlled by the interaction between electrons. At temperatures moderately lower than…
Formation of magnetically ordered state in the Kondo lattices is treated within the degenerate $s-f$ exchange and Coqblin-Schrieffer models. The Kondo renormalizations of the effective coupling parameter, magnetic moment and spin excitation…
We investigate the equilibrium and non-equilibrium transport through a quantum dot in the Kondo regime, embedded between a normal metal and a topological superconductor supporting Majorana bound states at its end points. We find that the…
The transport across a Kondo-correlated quantum dot coupled to two leads with independent temperatures and chemical potentials is studied using a controlled non-perturbative, and in this sense exact numeric treatment based on a hybrid…
The Kondo temperature of a magnetic impurity in a weakly disordered metal is distributed due to the randomness in the local exchange coupling, and the local electronic density of states (LDOS). We show that in a closed, phase coherent metal…
We investigate the duality in the Kondo model. Starting from the s-d model with the coupling constant $J$, the strong coupling model with the constant of 1/J is identified. The model shows the unitary limit of the conductance, $G=2 e^{2}/h$…