38 research outputs found
Photon-assisted electron transport through a three-terminal quantum dot system with nonresonant tunneling channels
We have studied the electron transport through a quantum dot coupled to three
leads in the presence of external microwave fields supplied to different parts
of the considered mesoscopic system. Additionally, we introduced a possible
nonresonant tunneling channels between leads. The quantum dot charge and
currents were determined in terms of the appropriate evolution operator matrix
elements and under the wide band limit the analytical formulas for
time-averaged currents and differential conductance were obtained. We have also
examined the response of the considered system on the rectangular-pulse
modulation imposed on different quantum dot-leads barriers as well as the
time-dependence of currents flowing in response to suddenly removed (or
included) connection of a quantum dot with one of the leads.Comment: 34 pages, 12 figure
Influence of microwave fields on the electron transport through a quantum dot in the presence of a direct tunneling between leads
We consider the time-dependent electron transport through a quantum dot
coupled to two leads in the presence of the additional over-dot (bridge)
tunneling channel. By using the evolution operator method together with the
wide-band limit approximation we derived the analytical formulaes for the
quantum dot charge and current flowing in the system. The influence of the
external microwave field on the time-average quantum dot charge, the current
and the derivatives of the average current with respect to the gate and
source-drain voltages has been investigated for a wide range of parameters.Comment: 28 Pages, 11 Postscript figure