Photon-assisted resonant transport through a multi-terminal mesoscopic system

The coherent transport through a multi-terminal mesoscopic system is investigated by using the nonequilibrium Green function technique. The sample is composed of two coupled Anderson impurities which are referred as the quantum dots. One dot is connected to N complete onedimensional wires, while the other one is linked to M wires. Each terminal is supplied an external oscillating field with potential V _α cos ω₀ t. The Landauer-Büttiker-like formulae are derived, and the resonant behaviors are discussed. We find these currents contributed by the channel-invariant and channel-variant tunneling processes. This effect signifies the tunneling electron perturbed by many photons. The resonant peaks are displayed analytically to be associated with the frequency, from which we observe that the main resonant peaks are modified by the frequency disturbings of photons. The locations of the peaks are determined by the spectrum levels of these dots, and at some points these peaks overlap to reduce the number of the peaks.