Related papers: Correlation Effects in Side-Coupled Quantum Dots
We calculate characteristic correlation functions for the Anderson model with additional phonon-assisted coupling to the odd conduction channel. This model describes, for example, the behavior of a molecule embedded between two electrodes…
The spin-polarized transport through a coherent strongly coupled double quantum dot (DQD) system is analyzed theoretically in the sequential and cotunneling regimes. Using the real-time diagrammatic technique, we analyze the current,…
We study the charge current transmitted through the correlated quantum dot characterized by a finite magnitude of the Coulomb interaction |U|. At low temperatures the correlations can lead to appearance of the spin (for U>0) or charge (for…
It is shown that the low-energy spin states of double quantum dots (DQD) with even electron occupation number $N$ possess the symmetry SO(4) similar to that of a rigid rotator familiar in quantum mechanics (rotational spectra of H$_2$…
We investigate thermoelectric properties of correlated quantum dots and molecules, described by a single level Anderson model coupled to conduction electron leads, by using Wilson's numerical renormalization group method. In the Kondo…
We investigate the Kondo effect in a double-quantum-dot which is capacitively coupled to a charge-Qubit. It is shown that due to this capacitive coupling, the bare inter-dot repulsive interaction in the double-quantum-dot is effectively…
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…
We describe the mechanism of charge-spin transformation in a double quantum dot (DQD) with even occupation, where a time dependent gate voltage v(t) is applied to one of its two valleys, whereas the other one is coupled to the source and…
We study two tunnel-coupled quantum dots each with a spin 1/2 and attached to leads in the Coulomb blockade regime. We study the interplay between Kondo correlations and the singlet-triplet exchange splitting $K$ between the two spins. We…
We present a theoretical study of a hybrid circuit-QED system composed of two semiconducting charge-qubits confined in a microwave resonator. The qubits are defined in terms of the charge states of two spatially separated double quantum…
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…
We predict a new type of the negative-$U$ Anderson impurity formed in a triple quantum dot. The two dots of the system behave as a negative-$U$ impurity preferring zero or double electron occupancy rather than single occupancy, and the…
We interpret the recent observation of a zero-bias anomaly in spin-1 quantum dots in terms of an underscreened Kondo effect. Although a spin-1 quantum dots are expected to undergo a two-stage quenching effect, in practice the log normal…
We investigate two equivalent capacitively and tunnel coupled quantum dots, each coupled to its own pair of leads. Local Holstein type electron-phonon coupling at the dots is assumed. To study many-body effects we use the finite-U…
We examine the properties of a dc-biased quantum dot in the Coulomb blockade regime. For voltages V large compared to the Kondo temperature T_K, the physics is governed by the scales V and gamma, where gamma ~ V/ln^2(V/T_K) is the…
The zero-bias anomaly at low temperatures, originated by the Kondo effect when an electric current flows through a system formed by a spin-$1/2$ quantum dot and two metallic contacts is theoretically investigated. In particular, we compare…
We observe a strong Kondo effect in a semiconductor quantum dot when a small magnetic field is applied. The Coulomb blockade for electron tunneling is overcome completely by the Kondo effect and the conductance reaches the unitary-limit…
We study transport through a triangle triple quantum dot connected to two noninteracting leads using the numerical renormalization group (NRG). The triangle has a high-spin ground state of S=1 caused by a Nagaoka ferromagnetism, when it is…
Strong correlation effects in a capacitively coupled double quantum-dot setup were previously shown to provide the possibility of both entangling spin-charge degrees of freedom and realizing efficient spin-filtering operations by static…
Designing coherent processes is essential for developing quantum information technologies. We study coherent dynamics of two spatially separated electrons in a coupled semiconductor double quantum dot (DQD), in which various two-qubit…