Quantum interference through parallel-coupled double quantum dots

The electronic transport is theoretically studied through a double quantum dot (DQD) system. With focus on the effects of the on-dot Coulomb repulsion U or the electron-phonon interaction(EPI) on the quantum interference in the parallel DQD, we find that if U is comparable with level separation in the parallel-coupled DQD, a new type of Fano interference between U-hybridized channels in the conductance spectra may appear and show new features; and if the EPI is significant only in one channel, as a prober of "which path" in quantum mechanics, the phonon channel won't interfere with the no-EPI channel. A closely related transport experiment is proposed to verify the prediction. (C) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.