Nonequilibrium Kondo effect in a multilevel quantum dot near the singlet-triplet transition

Article

关键词: MEAN-FIELD THEORY;    EVEN NUMBER;    MAGNETIC-FIELD;    ELECTRONS;   

DOI  :  10.1103/PhysRevB.66.113310

来源: SCIE

【 摘 要 】

The linear and nonlinear transport through a multilevel lateral quantum dot connected to two leads is investigated using a generalized finite-U slave-boson mean-field approach. For a two-level quantum dot, our calculation demonstrates a substantial conductance enhancement near the degeneracy point of the spin singlet and triplet states, a nonmonotonic temperature dependence of conductance, and a sharp dip and nonzero bias maximum of the differential conductance. These agree well with recent experiment observations. This two-stage Kondo effect in an out-of-equilibrium situation is attributed to the interference between the two energy levels.

【 授权许可】

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