Related papers: Kondo effect in systems with dynamical symmetries
We study the competition between the Kondo effect and the exchange interaction in the parallel double quantum dot(DQDs) system within an effective action field theory. The strong on-site Coulomb interactions in DQDs are treated by using the…
Quantum devices such as spin qubits have been extensively investigated in electrostatically confined quantum dots using high-quality semiconductor heterostructures like GaAs and Si. Here, we present the first demonstration of…
Electronic transport through a triple quantum dot system, with only a single dot coupled directly to external leads, is considered theoretically. The model includes Coulomb correlations in the central dot, while such correlations in the two…
An artificial atom with four electrons is driven through a singlet-triplet transition by varying the confining potential. In the triplet, a Kondo peak with a narrow dip at drain-source voltage V_ds=0 is observed. The low energy scale V_ds*…
We study the transport properties of a quantum dot embedded in an Aharonov-Bohm ring in the presence of spin-orbit interactions. Using a numerical renormalization group analysis of the system in the Kondo regime, we find that the…
The concept of dynamical symmetries is used for formulation of the renormalization group approach to the Kondo effect in the Anderson model with repulsive and attractive interaction $U$. It is shown that the generic local symmetry of the…
The exact and analytical low energy spectrum of the ferromagnetic Kondo lattice model on a complete graph extended with on-site repulsion $U$ is obtained in terms of a dynamical spl(2,1) supersymmetry in the limit of infinitely strong…
The transport properties of a double quantum-dot device with one of the dots coupled to perfect conductors are analyzed using the numerical renormalization group technique and slave-boson mean-field theory. The coupling between the dots…
We investigate the enhancement of the Kondo effect in quantum dots with an even number of electrons, using a scaling method and a mean field theory. We evaluate the Kondo temperature $T_K$ as a function of the energy difference between…
We investigate the influence of spin-orbit coupling on the Kondo effects in carbon nanotube quantum dots, using the numerical renormalization group technique. A sufficiently large spin-orbit coupling is shown to destroy the SU(4) Kondo…
We investigate the equilibrium and out-of-equilibrium Kondo effects in a single-level interacting quantum dot connected to two ferromagnetic leads. Within the non-crossing approximation, we calculate the total density of states (DOS), the…
The system of several (N) quantum dots coupled in parallel to the same single-mode conduction channel can be modelled as a single-channel N-impurity Anderson model. Using the generalized Schrieffer-Wolff transformation we show that near the…
We discuss a new entangled state that has been observed in the conduction across a quantum dot. At Coulomb blockade, electrons from the contacts correlate strongly to those localized in the dot, due to cotunneling processes. Because of the…
The Kondo effect originates from the spin exchange scattering of itinerant electrons with a localized magnetic impurity. Here, we consider generalization of Weyl-type electrons with their spin locked on a spherical Fermi surface in an…
The Kondo effect has been observed in a single gate-tunable atom. The measurement device consists of a single As dopant incorporated in a Silicon nanostructure. The atomic orbitals of the dopant are tunable by the gate electric field. When…
Quantum criticality in certain heavy-fermion metals is believed to go beyond the Landau framework of order-parameter fluctuations. In particular, there is considerable evidence for Kondo destruction: a disappearance of the static Kondo…
Nonequilibrium electronic transport through a quantum dot coupled to ferromagnetic leads (electrodes) is studied theoretically by the nonequilibrium Green function technique. The system is described by the Anderson model with arbitrary…
We discuss the Kondo effect for isospin-exchange interaction between a $\bar{D}$, $B$ meson and a valence nucleon in charm/bottom atomic nuclei including the discrete energy-levels for valence nucleons. To investigate the binding energy by…
We show here the existence of the indirect coupling of electron and magnetic or nuclear ion spins in self-assembled quantum dots mediated by electron-electron interactions. With a single localized spin placed in the center of the dot, only…
We investigate the Josephson effect through a two-level quantum dot with an exchange coupling between two dot electrons. We compute the superconducting phase relationship and construct the phase diagram in the superconducting gap--exchange…