Related papers: Low-temperature behavior of transmission phase shi…
We report on the direct observation of the transmission phase shift through a Kondo correlated quantum dot by employing a new type of two-path interferometer. We observed a clear $\pi/2$-phase shift, which persists up to the Kondo…
We report on the phase measurements on a quantum dot containing a single electron in the Kondo regime. Transport takes place through a single orbital state. Although the conductance is far from the unitary limit, we measure for the first…
The transmission phase through a quantum dot with few electrons shows a complex, non-universal behavior. Here we combine configuration-interaction calculations ---treating rigorously Coulomb interaction--- and the Friedel sum rule to…
We investigate a quantum phase transition (QPT) in quantum point contacts by analyzing the gate-voltage-dependent quasiparticle energy at the Fermi level at zero temperature. This energy is computed using the local density of states at the…
We investigate the appearance of pi lapses in the transmission phase theta of a two-level quantum dot with Coulomb interaction U. Using the numerical and functional renormalization group methods we study the entire parameter space for…
The complex transmission amplitude -- both magnitude and phase -- of a quantum dot (QD) with Kondo correlation was measured near the unitary limit. Contrary to previous phase measurements, performed far from this limit [Ji et al., Science…
We report a strong Kondo effect (Kondo temperature ~ 4K) at high magnetic field in a selective area growth semiconductor quantum dot. The Kondo effect is ascribed to a singlet-triplet transition in the ground state of the dot. At the…
A system with equal number of positive and negative charges confined in a box with a small but finite thickness is modeled as a function of temperature using mesoscale numerical simulations, for various values of the charges. The Coulomb…
We calculate the conductance through a quantum dot weakly coupled to metallic leads, modeled by the spin-1/2 Anderson model with finite Coulomb repulsion $U$. We adopt the non-crossing approximation method in its finite-$U$ extension…
The thermoelectric properties of strongly correlated quantum dots, described by a single level Anderson model coupled to conduction electron leads, is investigated using Wilson's numerical renormalization group method. We calculate the…
Thermodynamic properties of the one-dimensional Kondo lattice model at half-filling are studied by the density matrix renormalization group method applied to the quantum transfer matrix. Spin susceptibility, charge susceptibility, and…
Kondo temperature is standardly defined from the local zero-temperature susceptibility in the regime of strong electron correlations as a new scale controlling the low-temperature asymptotics of thermodynamic quantities. We show by using a…
The tunneling conductance is calculated as a function of the gate voltage in wide temperature range for the single quantum dot systems with Coulomb interaction. We assume that two orbitals are active for the tunneling process. We show that…
We study the coherent properties of transmission through Kondo impurities, by considering an open Aharonov-Bohm ring with an embedded quantum dot. We develop a novel many-body scattering theory which enables us to calculate the conductance…
Mesoscopic systems constitute appealing platforms to study many-body physics with light and matter degrees of freedom. The Kondo effect refers to the screening of a spin-1/2 impurity by a cloud of conduction electrons, then forming a…
We analyze the transport properties of a double quantum dot device in the side-coupled configuration. A small quantum dot (QD), having a single relevant electronic level, is coupled to source and drain electrodes. A larger QD, whose…
We report anomalous critical transport behavior in a GaAs structure containing a dense array of ErAs quantum dots. The structure displays a voltage (electric field)-controlled insulator-to-metal transition and strong hysteresis in the…
Besides the usual conductance plateaus at multiples of 2e2/h, quantum point contacts typically show an extra plateau at ~ 0.7(2e2/h), believed to arise from electron-electron interactions that prohibit the two spin channels from being…
Kondo effect in the vicinity of a singlet-triplet transition in a vertical quantum dot is considered. This system is shown to map onto a special version of the two-impurity Kondo model. At any value of the control parameter, the system has…
We demonstrate a tunable Kondo effect realized in small quantum dots. We can switch our dot from a Kondo impurity to a non-Kondo system as the number of electrons on the dot is changed from odd to even. We show that the Kondo temperature…