En las fronteras de la Materia Condensada

There has been a great effort dedicated to the study of quantum transport through quantum dots (QD) due to its similarities with a real atom. Most of the properties of highly correlated electrons, highly confined by the atomic potential, have been predicted to be present and experimentally measured in QD.
The enormous advantage of studying the electronic properties in a QD compared to real atoms results from the possibility of driving the system through different regimes by simply changing, in a continuous way, the external potential that define the dot. The Kondo effect, recently measured in these systems, is the clearest example of the equivalence between a real atom and a QD.
We will discuss several aspects of the Kondo effect appearing in QDs as it is the case of the so called "quantum transition". This is a phenomenon, which some real Ce compounds suffer by tuning the spin-spin Kondo correlation and the anti-ferromagnetic spin-spin correlation between the atoms applying an external or chemical pressure. In our case this phenomenon is studied analyzing the transport properties derived from a system of two coupled QDs as a function of the inter-dot coupling and temperature. We theoretically study as well the transport properties of a QD connected to two leads which suffers a transition between a Kondo spin S=1 ground state and a S = 0 non-Kondo state as a function of an external magnetic field We were able to explain the experimental results recently obtained for this system.
We will present a numerical formalism, which results to provide a very accurate solution to the transport problem of these highly correlated systems.