Regensburg 2007 – wissenschaftliches Programm

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TT: Fachverband Tiefe Temperaturen

TT 18: Nanoelectronics I - Quantum Dots, Wires, Point Contacts

TT 18.1: Vortrag

Mittwoch, 28. März 2007, 14:00–14:15, H19

Charge transfer statistics through multi-terminal Kondo and Anderson impurities — •Andrei Komnik¹, Thomas Schmidt¹, and Alexander Gogolin² — ¹Physikalisches Institut, Albert-Ludwigs-Universität Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg — ²Department of Mathematics, Imperial College London, 180 Queen's Gate, London SW7 2AZ, United Kingdom

We investigate the charge transfer statistics through a quantum dot in the Kondo regime coupled to an arbitrary number of terminals. Using the effective Hamiltonian valid at energies far below the Kondo temperature we calculate the generating function for the full counting statistics (FCS) perturbatively in the leading irrelevant operators. The transport seems to be mediated not only by single electron tunnelling but by correlated transport of electron pairs as well. We propose a measurement of cross correlations of Hanbury Brown and Twiss type in a multi-terminal geometry which is able to explicitly discern both processes in experiments. Furthermore we make predictions for generalised Fano factors to be universal and parameter-free. By comparison of perturbative expansions for weak and strong couplings we make predictions for the FCS of a more realistic multi-terminal Anderson impurity model, which are valid at all energy scales as long as the applied transport voltage is small.