Transport in a mesoscopic ring with a quantum dot: from the Coulomb\n blockade regime to the Kondo effect

The system described in this work consists of a quantum dot inserted in a\nmesoscopic ring threaded by a magnetic flux. Our aim is to present a complete\ndescription for this device and to predict the physics of a experiment with\nthese features.\n We have proposed a model that takes into account the conditions that are\nusual in experiments with quantum dots and mesoscopic systems. In order to\nsolve the model, we develop a methodology to find the Green's functions of the\nsystem by means of proper approximations.\n This system presents persistent currents as a function of a gate potential\napplied to the quantum dot. We have studied the influence of both the\ninteraction between electrons and the hybridization between the ring and the\ndot. We have found several regimes that describe different physical phenomena\ninvolved in the system. These regimes range from the phenomenon of Coulomb\nBlockade (in the high correlation limit) to a quasi non interacting regime.\nBetween these two limits we have found an intermediate regime where the Kondo\neffect shows up.\n