Leakage current of a superconductor–normal metal tunnel junction connected to a high-temperature environment
Leakage current of a superconductor–normal metal tunnel junction connected to a high-temperature environment
We consider a voltage-biased normal metal-insulator-superconductor (NIS) tunnel junction, connected to a high-temperature external electromagnetic environment. This model system features the commonly observed subgap leakage current in NIS junctions through photon-assisted tunneling which is detrimental for applications. We first consider a NIS junction directly coupled to the environment and analyze …