Issue
EPL
Volume 83, Number 3, August 2008
Article Number 38002
Number of page(s) 6
Section Interdisciplinary Physics and Related Areas of Science and Technology
DOI http://dx.doi.org/10.1209/0295-5075/83/38002
Published online 18 July 2008
EPL, 83 (2008) 38002
DOI: 10.1209/0295-5075/83/38002

Photon-assisted Fano and Kondo resonance in an Aharonov-Bohm interferometer

H. Gao and H. K. Zhao

Department of Physics, Beijing Institute of Technology - Beijing 100081, China

zhaohonk@yahoo.com

received 24 February 2008; accepted in final form 12 June 2008; published August 2008
published online 18 July 2008

Abstract
We have investigated the photon-assisted tunneling through an ultra-small quantum dot (QD) embedded Aharonov-Bohm (AB) interferometer under the perturbation of external microwave fields (MWFs). The tunneling current is derived by using nonequilibrium Green's function technique. The local density of state at finite Coulomb interaction, the differential conductance resonance, current oscillation with respect to AB flux influenced by the nature of the QD and bridge channel have been studied. The MWFs generate novel resonant and Fano structures, which are sensitively dependent on the irradiation approach of MWFs. Novel Kondo peaks can be seen due to the photon-assisted tunneling, and the asymmetric Fano structure also exhibits itself in the photon-assisted satellite peaks and valleys. Our system can be employed as an interferometer to produce novel output signals by controlling the applied MWFs.

PACS
85.35.-p - Nanoelectronic devices.
73.23.-b - Electronic transport in mesoscopic systems.
73.21.La - Quantum dots.

© EPLA 2008