Related papers: Spin-orbital Kondo effect in a parallel double qua…
The system described in this work consists of a quantum dot inserted in a mesoscopic ring threaded by a magnetic flux. Our aim is to present a complete description for this device and to predict the physics of a experiment with these…
We present measurements on the Kondo-effect in a small quantum dot connected strongly to one lead and weakly to the other. The conductance of the dot reveals an offset of the Kondo resonance at zero magnetic field. While the resonance…
Electron tunneling through a system formed by two coupled quantum dots in a parallel geometry is considered within a generalized Anderson model. The dots are assumed to have nearly equal radii but different (and tunable) gate voltages. In…
We analyze the equilibrium transport properties of underscreened Kondo effect in the case of a two-level quantum dot coupled to ferromagnetic leads. Using the numerical renormalization group (NRG) method, we have determined the gate voltage…
We study strongly correlated states in triangular artificial atoms. Symmetry-driven orbital degeneracy of the single particle states can give rise to an SU(4) Kondo state with entangled orbital and spin degrees of freedom, and a…
Quantum spin transport is studied in an interacting quantum dot. It is found that a conductance "plateau" emerges in the non-linear charge conductance by a spin bias in the Kondo regime. The conductance plateau, as a complementary to the…
We study a small spin-degenerate quantum dot with even number of electrons, weakly connected by point contacts to the metallic electrodes, and subject to an external magnetic field. If the Zeeman energy B is equal to the single-particle…
We consider electron transport along a single-mode channel which is in contact, via tunnel junctions in its walls, with two quantum dots. Electron tunneling to and from the dots contributes to the electron backscattering, and thus modifies…
In a tunneling experiment across a quantum dot it is possible to change the coupling between the dot and the contacts at will, by properly tuning the trasparency of the barriers and the temperature. Gate voltages allow for changes of the…
The effective interaction between magnetic impurities in metals that can lead to various magnetic ground states often competes with a tendency for electrons near impurities to screen the local moment (Kondo effect). The simplest system…
We study electron transport through a multi-level quantum dot with Rashba spin-orbit interaction in the presence of local Coulomb repulsion. Motivated by recent experiments, we compute the level splitting induced by the spin-orbit…
We study the energy spectrum of symmetric double quantum dots in narrow-gap carbon nanotubes with one and two electrostatically confined electrons in the presence of spin-orbit and Coulomb interactions. Compared to GaAs quantum dots, the…
System of two quantum dots attached to external electrodes is considered theoretically in orbital Kondo regime. In general, the double dot system is coupled via both Coulomb interaction and direct hoping. Moreover, the indirect hopping…
We realize a strongly coupled double quantum dot in a single all-organic molecule by introducing a non-conjugated bridge in between two identical conjugated moieties. Spin-1/2 Kondo and Kondo enhanced low-energy excitations for respectively…
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…
We show a detailed investigation of the split Kondo effect in a carbon nanotube quantum dot with multiple gate electrodes. It is found that the splitting decreases for increasing magnetic field, to result in a recovered zero-bias Kondo…
We consider the spin and orbital Kondo effect in a parallel arrangement of two strongly electrostatically coupled quantum dots. Increasing the exchange of electrons between the dots through the attached leads induces the transition between…
A scenario for the formation of symmetry protected non-Fermi-liquid (NFL) Kondo effect (KE) with spin variable enumerating Kondo channels is suggested and worked out. In doubly occupied symmetric triple quantum dot within parallel geometry,…
The Kondo effect in coupled quantum dots is investigated from the viewpoint of transmission spectroscopy using the slave-boson formalism of the Anderson model. The antiferromagnetic spin-spin coupling $J$ between the dots is taken into…
Based on ab-initio calculations we identify possible scenarios for the Kondo effect due to Co ad-atoms on graphene. General symmetry arguments show that for magnetic atoms in high-symmetry positions, the Kondo effect in graphene is…