Electron Transport through Double Quantum Dot: from SU(4) Kondo to SU(2) Symmetry
D. Sztenkiel and R. Świrkowicz
Faculty of Physics, Warsaw University of Technology, Koszykowa 75, 00-662 Warsaw, Poland
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Received: 9 06 2007;
Electron transport across two capacitively coupled quantum dots in a parallel geometry is theoretically studied in the non-linear response regime with spin and orbital degrees of freedom taken into account and the Kondo effect induced by on-site and inter-dot Coulomb correlations is analyzed. For a system with each dot symmetrically coupled to a separate set of electrodes a well-defined spin and orbital contributions to zero-bias Kondo resonance are obtained. The Kondo peak splits if spin and/or orbital degeneracies are removed. A suppression of the orbital Kondo anomaly due to orbital asymmetry and channel mixing effects is discussed.
DOI: 10.12693/APhysPolA.112.387
PACS numbers: 73.63.Kv, 72.15.Qm, 73.40.Gk, 73.23.Hk