Nonequilibrium Steady States and Fano-Kondo Resonances in an AB Ring with a Quantum Dot(Condensed matter: electronic structure and electrical, magnetic, and optical properties)

概要

論文の詳細を見る
Electron transport through a strongly correlated quantum dot (QD) embedded in an Aharonov-Bohm (AB) ring is investigated with the aid of the finite-U slave-boson mean-field (SBMF) approach extended to nonequilibrium regime. A nonequilibrium steady state (NESS) of the mean-field Hamiltonian is constructed with the aid of the C^*-algebraic approach for studying infinitely extended systems. In the linear response regime, the Fano-Kondo resonances and AB oscillations of the conductance obtained from the SBMF approach are in good agreement with the numerical renormalization group (NRG) results of Hofstetter et al. by using twice larger Coulomb interaction in the unit of the dot linewidth. At zero temperature and finite bias voltage, the resonance peaks of the differential conductance tend to split into two. At low bias voltage, the split of the asymmetric resonance can be observed as an increase of the conductance plateau. We also found that the differential conductance has zero-bias maximum or minimum depending on the background transmission via direct tunneling between the electrodes.
社団法人日本物理学会の論文
2006-09-15