Charge and spin supercurrents in magnetic Josephson junctions with spin filters and domain walls

Article

关键词: EXCHANGE FIELD;    FERROMAGNET;    SUPERCONDUCTIVITY;    EQUATIONS;    STATES;   

DOI  :  10.1103/PhysRevB.105.094517

来源: SCIE

【 摘 要 】

We analyze theoretically the influence of domain walls (DWs) on the DC Josephson current in magnetic superconducting Sm/Fl/F/Fl/Sm junctions. The Josephson junction consists of two ???magnetic??? superconductors Sm (superconducting film covered by a thin ferromagnetic layer), spin filters Fl, and a ferromagnetic layer F with or without DW(s). The spin filters Fl allow electrons to pass with one specific spin orientation, such that the Josephson coupling is governed by a fully polarized long-range triplet component. In the absence of DW(s), the Josephson and spin currents are nonzero when the right and left filters, Flr,l, pass electrons with equal spin orientation and differ only by a temperature-independent factor. They become zero when the spin orientation of the triplet Cooper pairs passing through the Flr,l have opposite directions. Furthermore, for the different chiralities of the injected triplet Cooper pairs, the spontaneous currents arise in the junction yielding a diode effect. Once a DW is introduced, it reduces the critical Josephson current Ic in the case of equal spin polarization and makes it finite in the case of opposite spin orientation. The critical current Ic is maximal when the DW is in the center of the F film. A deviation of the DW from the center generates a force that pushes the DW to the center of the F film. In addition, we consider the case of an arbitrary number N of DWs, with the case N = 2 resembling a magnetic skyrmion.

【 授权许可】

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