Interference Effect of Beam Splitter Current in Iron-Pnictide Superconductors

Abstract

We consider a Cooper pair beam splitter for Iron-Pnictide superconductor and calculate the entangled electron-hole current. We investigate the interplay of various physical parameters such as doping at electron and hole pockets as well as non-zero nesting between the electron and hole pocket. We find that in the absence of magnetic order, the current due to hole pocket and electron pocket add up ordinarily. However in the presence of magnetic ordering the two currents take part in characteristic interference effect to modify the resultant current significantly. This interference effect manifests itself in non-monotonous and oscillatory nature of beam splitter current. We investigate in details this non-monotonicity with the chemical potential as well as nesting vectror $|\bf q|$. We also investigate the evolution of density of states with system parameters and correlate it with the beam-splitter current. Further we enumerate the relevant parameter space where the efficiency of such beam splitter set up is enhanced. Our finding can be useful in experimental determination or verification of co-existence phase in Iron-Pnictide superconductors and has potential applications in realizing quantum gates or switches.