Quantum Transport through Quantum Dot with Electron-Phonon Interaction

Abstract

We have studied the quantum transport through a quantum dot with electron-phonon interaction. For a generic model which is widely used to explain phononcoupled electron transport in quantum dots and single molecule junctions. We haveshown that the system exhibit pronounced bistability even in out of equilibriumsituations when the value of the bias is far from the linear response regime. Theanalysis revealed that the bistability increased for decreasing phonon frequency anddepended on the electron-phonon coupling. We have developed an approach basedon reduced density matrix formalism. The formalism is combined with themultilayer multi configuration time dependent Hartree method to numericallyconverge the memory Kernel at short times until it decays and infer from it thedynamics of the system at longer times and the approach to steady state. Therelaxation to steady state and the appearance of the bistability depended on thephonon frequency and the strength of the electron-phonon coupling. We have foundthat the phenomenon persisted over time scale. The obtained results were found ingood agreement with previously obtained results