Single Charge Current in a Normal Mesoscopic Region Attached to Superconductor Leads via a Coupled Poisson Nonequilibrium Green Function Formalism

Figure 15

The contour C_K=C_K−∪C_K+ runs on the real axis, but for clarity its two branches C_K− and C_K+ are shown slightly away from the real axis. The contour C_K runs from 𝑡₀ and returns to 𝑡₀.