Related papers: Kondo effect in single-molecule magnet transistors
We present theoretical results for a Kondo-lattice model with spin-1/2 localized moments, including both the intrasite Kondo coupling and an intersite antiferromagnetic exchange interaction, treated within an extended mean-field…
A dilute concentration of magnetic impurities can dramatically affect the transport properties of an otherwise pure metal. This phenomenon, known as the Kondo effect, originates from the interactions of individual magnetic impurities with…
Transport through molecular magnets is studied in the regime of strong coupling to the leads. We consider a resonant-tunneling model where the electron spin in a quantum dot or molecule is coupled to an additional local, anisotropic spin…
We introduce a two-band Kondo-lattice model to describe ferromagnetic half-metals with local magnetic moments. In a model study, the electronic and magnetic properties are presented by temperature dependent magnetization curves,…
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…
Magnetic switching of a single-molecule magnet (SMM) due to spin-polarized current is investigated theoretically. The charge transfer between the electrodes takes place via the lowest unoccupied molecular orbital (LUMO) of the SMM.…
We theoretically study enhancement mechanisms of the Kondo effect in multilevel quantum dots. In quantum dots fabricated on semiconductors, the energy difference between discrete levels \Delta is tunable by applying a magnetic field. With…
Magnetic and charge susceptibilities in the Kondo lattice are derived by the continuous-time quantum Monte Carlo (CT-QMC) method combined with the dynamical mean-field theory. For a weak exchange coupling J and near half filling of the…
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…
We investigate the Josephson effect through a molecular quantum dot magnet connected to superconducting leads. The molecule contains a magnetic atom, whose spin is assumed to be isotropic. It is coupled to the electron spin on the dot via…
We study one dimensional {\it extended} Kondo lattice model, described by the $t-J$ Hamiltonian for conduction electrons away from half filling and the Heisenberg Hamiltonian for localized spins at half filling. Following…
The ability to make electrical contact to single molecules creates opportunities to examine fundamental processes governing electron flow on the smallest possible length scales. We report experiments in which we controllably stretch…
The coherent spin dependent transport through a set of two capacitively coupled quantum dots placed in a magnetic field is considered within the equation of motion method. The magnetic field breaks the spin degeneracy. For special choices…
Progress in the fabrication of nanometer-scale electronic devices is opening new opportunities to uncover the deepest aspects of the Kondo effect, one of the paradigmatic phenomena in the physics of strongly correlated electrons. Artificial…
We investigate a system of three tunnel-coupled semiconductor quantum dots in a triangular geometry, one of which is connected to a metallic lead, in the regime where each dot is essentially singly occupied. Both ferro- and…
Single-ion magnetic anisotropy in molecular magnets leads to spin flip excitations that can be measured by inelastic scanning tunneling microscope (STM) spectroscopy. Here I present a semi ab initio scheme to compute the spectral features…
The Kondo effect is a striking consequence of the coupling of itinerant electrons to a quantum spin with degenerate energy levels. While degeneracies are commonly thought to arise from symmetries or fine-tuning of parameters, the recent…
We show how the charge input signal applied to the gate electrode in a double and triple quantum dot may be converted to a pulse in the Kondo cotunneling current being a spin response of a nano-device under a strong Coulomb blockade. The…
We explore theoretically the spin transport in nanostructures consisting of a gold quantum dot bridging nonmagnetic electrodes and two Mn12-Ph single molecule magnets (SMMs) that are thiol-bonded to the dot but are not in direct contact…
In Kondo insulators the many-body Kondo lattice effect drives the formation of bands containing heavy charge carriers with a hybridization gap, leading to insulating properties. These renormalized bands can host non-trivial topologies…