Electron Transport through Double Quantum Dot: from SU(4) Kondo to SU(2) Symmetry
نویسندگان
چکیده
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.
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