Photon-Assisted Shot Noise in Normal Metal-Insulator-Superconductor Heterostructures

Abstract

Photon-assisted electron transport in mesoscopic heterostructures is studied via a scattering approach. The nonequilibrium current fluctuations of normal metal-insulator-superconductor systems under illumination with monochromatic microwaves have been calculated. Using a time-periodic potential applied across the tunnel junction we model the emission and absorption of photons. We have concluded that the photon-assisted shot noise decreases when the insulating barrier becomes more transparent. The voltage dependence of the shot-noise power as a function of microwave frequency has been investigated as well.