The smallest system for storing and processing information using the magnetic states is a single atom. The magnetic anisotropy plays an essential role here, since it defines the energy barrier between the degenerate ground states of the spin. We have studied for the role of the magnetic anisotropy in single magnetic atoms adsorbed on an ultra-thin insulating barrier on metal surfaces. We have established under which conditions the Kondo effect can occur.
COBISS.SI-ID: 22427175
The electronic transport through a molecule in the Kondo regime is investigaed. The tunneling between the electrode and the molecule is asymmetrically modulated by the oscillations of the molecule. If the molecule gets closer to one of the electrodes the tunneling to that electrode will increase and at the critical value of the electron-phonon coupling an unstable two-channel Kondo fixed point is found.
COBISS.SI-ID: 2143332
Entanglement of spins is analyzed for two electrons extracted from a mixed many electron state by projecting onto the two-electron subspace. As an example, the thermal entanglement for a qubit pair with an anisotropic Heisenberg and the Dzyaloshinskii-Moriya interactions in an inhomogeneous magnetic field is given analytically.
COBISS.SI-ID: 22644775
The deviations from the Fano resonance profile in scattering on weakly side-coupled quantum dots can only arise from correlation or from thermal effects; in general, both sources of deviations are important. The antiresonance in the transport experiments in side-coupled double quantum dot may be explained in terms of the two-stage Kondo screeningwith the experimental temperature between the two different Kondo scales.
COBISS.SI-ID: 23480103
We calculate the electronic structure of Sr2RuO4, treating correlations within dynamical mean-field theory. The approach successfully reproduces several experimental results and explains the key properties of this material: the anisotropic mass renormalization of quasiparticles and the crossover into an incoherent regime above a low temperature scale. While the orbital differentiation originates from the proximity of the van Hove singularity, strong correlations are caused by the Hund’s coupling.
COBISS.SI-ID: 24640039