Photon-assisted mesoscopic transport through a quantum dot-carbon nanotube system perturbed by microwave fields

We have investigated the coherent mesoscopic transport through the system with a quantum dot coupled to single-wall carbon nanotubes (CN-QD-CN) interfered by microwave fields (MWFs). The investigation focuses on the tunneling behaviors induced by the double coherent MWFs and the nature of CN leads. The incoherent fields induce the tunneling current possessing symmetric resonant behaviors. The coherent fields induce the asymmetric tunneling current resulting from the interference of tunneling current branches to form asymmetric photon-assisted net current. The quantum leads possess specific density of state (DOS) structure, and the matching-mismatching behavior takes important role in the mesoscopic transport. The feature of coupled MWFs and the connected quantum wires together control the characteristics of the mesoscopic system. (C) 2004 Elsevier B.V. All rights reserved.