Nonlocal and local transports in a silicene-based superconducting double-barrier tunnel junction with two ferromagnetic electrodes

Abstract

We investigate theoretically the nonlocal and local transport properties of relativistic electrons tunnelling through a silicene-based superconducting double-barrier sandwiched between two ferromagnets in the presence of an external electric field. Based on the Blonder-Tinkham-Klapwijk formalism, the crossed Andreev reflection (CAR), nonlocal, and local differential conductances are numerically calculated by using a transfer-matrix method. We find that the energy regions of both the exclusive elastic cotunneling and exclusive CAR processes are gradually broadened as the exchange splitting energy increases. The CAR, nonlocal, and local differential conductances have a symmetrical distribution with respect to the external electric field and the nonlocal transport process is suppressed when the superconducting gap is large enough. Furthermore, the CAR, nonlocal, and local differential conductances exhibit periodic oscillatory behavior by increasing either the superconducting or insulating barrier potential, along with typical quasiperiodic oscillations as the middle insulating barrier width increases.