Persistent currents in a superconductor/normal loop

Abstract

The persistent currents of normal/superconducting loop modulated by the phase shift, η, of electron wave functions due to Andreev reflection process is studied. The persistent currents show the periodicity of the superconducting unit flux quantum, Φ0/2, regardless of the system parameters, when the energy splitting E is smaller than the pair potential Δ. In the limit, E ≥ Δ, the persistent currents take the Josephson type formula,. © 2006 Springer Science+Business Media, Inc.