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تسجيل مستخدم جديدBeam splitter geometry for Iron-Pnictide materials
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We consider a Cooper pair beam splitter for Iron-Pnictide $S_{+-}$ 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. In general we find that the presence of magnetic ordering decreases the beam splitter current by a factor of one hundred in comparison to pure BCS superconductor in two dimensions. For equal size electron-hole pocket and zero nesting we find that the beam-splitter current in general depends non-monotonically on the chemical potentials at electron and hole pockets. For non-zero nesting at a fixed chemical potential the current also varies non-monotonically with nesting vector $|bf q|$. This non-monotonous or oscillatory behavior is attributed to inter-dependency of density of states at hole and electron pocket due to coupling between the electron and hole pockets. Our finding can be useful in experimental determinations or verification of co-existence phase in Iron-Pnictide superconductors and has potential applications in realizing quantum gates or switches.
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