MESOSCOPIC TRANSPORT THROUGH A QUANTUM-DOT-EMBEDDED AHARONOV–BOHM RING THREADED WITH AC FLUX

Abstract

The electron transporting through a mesoscopic ring embedded with one quantum dot and threaded by dc and ac magnetic fluxes is investigated by employing the Keldysh nonequilibrium Green function technique. The tunneling current and differential conductance are derived to show the Aharonov–Bohm-like effect induced by external magnetic fluxes. The multi-channel ring and multi-level quantum dot system is studied. The quenching and nonmonotone effects versus the magnitude of ac flux are revealed in differential conductance. This signifies that at some values of ac flux, the tunneling current may be suppressed or enhanced. The differential conductance oscillation and I-V characteristics are studied numerically at zero temperature. The aperiodically nonmonotonical conductance versus the magnitude of ac flux, multi-channel negative differential conductance, photon-electron pump effect are also observed.