| speaker: | Gergely Zarand Budapest, Hungary |
| time: | Mo., 20.08, 9:50-10:40 |
We discuss several mesoscopic realizations of quantum critical states. We first show how the two-impurity Kondo state can be approached in double quantum-dot systems. Contrary to common belief, the corresponding fixed point is robust against particle-hole symmetry breaking and various other asymmetries, and is only unstable to charge transfer between the two dots. We propose an experimental set-up where such charge transfer processes are suppressed, allowing a controlled approach to this quantum critical state and discuss transport and scaling properties in the vicinity of this critical state. We shall also present theoretical results for the AC transport properties of the double dot structure realized recently by David Goldhaber-Gordon's group at Stanford, where another prototypical non-Fermi liquid state, the 2-channel Kondo state has been observed. Finally, if time allows, we shall also discuss another dissipation-driven charge localization transition in a quantum dot.