相关论文: Kondo Effect in Quantum Dots Coupled to Luttinger …
We review our recent studies on the Kondo effect in the tunneling phenomena through quantum dot systems. Numerical methods to calculate reliable tunneling conductance are developed. In the first place, a case in which electrons of odd…
By properly generalizing Nozie`res' Fermi liquid theory, we construct an Hamiltonian approach to the scattering of conduction electrons off a spin-1/2 impurity in the ovescreneed Kondo regime, as T -> 0. We derive the S-matrix at the…
Correlation effects on electron transport through a system of T-shaped double-dots are investigated, for which only one of the dots is directly connected to the leads. We evaluate the local density of states and the conductance by means of…
We investigate low-temperature transport characteristics of a side-coupled double quantum dot where only one of the dots is directly connected to the leads. We observe Fano resonances, which arise from interference between discrete levels…
The zero bias conductance of quantum dots coupled to ferromagnetic leads is investigated. In the strong coupling regime, it is found that the conductance is a non-monotonic function of the angle between the magnetisation directions in the…
Spin-polarized transport through a quantum dot strongly coupled to ferromagnetic electrodes with non-collinear magnetic moments is analyzed theoretically in terms of the non-equilibrium Green function formalism. Electrons in the dot are…
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…
Non-equilibrium Green's function technique has been used to calculate spin-dependent electronic transport through a quantum dot in the Kondo regime. The dot is described by the Anderson Hamiltonian and is coupled either symmetrically or…
The Kondo effect emerges when a localized spin is screened by conduction electrons, giving rise to a strongly-correlated many-body ground state. In this work, we investigate this phenomenon in a GaAs/AlGaAs quantum dot, focusing on the…
The Kondo effect in quantum dots attached to ferromagnetic leads with general polarization directions is studied combining poor man scaling and Wilson's numerical renormalization group methods. We show that polarized electrodes will lead in…
Recent experiments performed on weakly pinched quantum point contacts, have shown a resistance that tend to decrease at low source drain voltage. We show that enhanced Coulomb interactions, prompt by the presence of the point contact, may…
The interplay between vibrational modes and Kondo physics is a fundamental aspect of transport properties of correlated molecular conductors. We present theoretical results for a single molecule in the Kondo regime connected to left and…
Numerical analysis of the simplest odd-numbered system of coupled quantum dots reveals an interplay between magnetic ordering, charge fluctuations and the tendency of itinerant electrons in the leads to screen magnetic moments. The…
Transport measurements at cryogenic temperatures through a few electron top gated quantum dot fabricated in a silicon/silicon-germanium heterostructure are reported. Variations in gate voltage induce a transition from an isolated dot toward…
Kondo correlation in a spin polarized quantum dot (QD) results from the dynamical formation of a spin singlet between the dot's net spin and a Kondo cloud of electrons in the leads, leading to enhanced coherent transport through the QD. We…
In this paper we study the thermopower of a quantum dot connected to two leads in the presence of Kondo correlation by employing a modified second-order perturbation scheme at nonequilibrium. A simple scheme, Ng's ansatz [Phys. Rev. Lett.…
We study the fate of the Kondo effect with one-dimensional conduction baths at very low densities, such that the system explores the bottom of the conduction band. This can involve either finite low densities, or a small number of fixed…
The Kondo effect is a key many-body phenomenon in condensed matter physics. It concerns the interaction between a localised spin and free electrons. Discovered in metals containing small amounts of magnetic impurities, it is now a…
We consider a quantum dot coupled to two BCS superconductors with same gap energies $\Delta$. The transport properties are investigated by means of infinite-$U$ noncrossing approximation. In equilibrium density of states, Kondo effect shows…
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…