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TT: Tiefe Temperaturen
TT 37: Transport - Fluctuations and Noise
TT 37.7: Vortrag
Mittwoch, 9. März 2005, 11:45–12:00, TU H3027
Shot noise in tunneling transport through molecules and coupled quantum dots — •Jasmin Aghassi1,2, Axel Thielmann1, Matthias Hettler1, and Gerd Schön1,2 — 1Forschungszentrum Karlsruhe, Institut für Nanotechnologie, Postfach 3640, 76021 Karlsruhe — 2Universität Karlsruhe, Institut für Theoretische Festkörperphysik
We consider charge transport through a nanoscopic object such as single molecules or coupled quantum dots, that is weakly coupled to metallic electrodes. We explicitly account for the electronic interactions and the resulting many-body states of the molecule/quantum dots, and allow for relaxation of the excited states. The current-voltage characteristics as well as the current noise are calculated within first-order perturbation expansion in the coupling strengths. For the case of a semi-quantitative model of benzene we predict negative-differential-conductance accompanied with super-poissonian noise. For a series coupled quantum dots, we analyze the shot noise in the various regimes of transport depending on the inter-dot coupling and participating many-body states.