Abstract: | We study the effects of infrared radiation on a two-dimensional Bardeen-Cooper-Schrieffer superconductor coupled with a normal metal substrate through a tunneling barrier.The phase transition is analyzed by inspecting the stability of the system against perturbations of pairing potentials.We find an oscillating gap phase with a frequency not directly related to the radiation frequency,but instead resulting from the asymmetry of electron density of states of the system as well as the tunneling amplitude.When such a superconductor is in contact with another superconductor,gives rise to an unusual alternating Josephson current. |