Photon-assisted quasiparticle transport and Andreev transport through an interacting quantum dot

Resonant tunneling through a quantum dot coupled to superconducting reservoirs in the presence of time-dependent external voltage has been studied. A general formula of the current is derived based on the nonequilibrium Green’s-function technique. Using this formula photon-assisted quasiparticle transport has been investigated for the quantum dot connected to superconductors. In addition, resonant Andreev transport through a strongly correlated quantum dot connected to a normal metallic lead and a superconducting lead is studied.