Modulation of the properties of a low-Tc superconductor by anisotropic ferromagnetic particles

In this work we study the modulation of superconductivity in combinatorial films (CFs) that are constructed by anisotropic CoPt ferromagnetic particles (FPs) randomly embedded in high-quality Nb layers of thickness 200 nm. In the constructed CFs the FPs are embedded in only half of the Nb layers. In this way we studied the modulation of superconductivity directly by performing transport measurements on the hybrid and pure superconducting areas of the CFs simultaneously under the application of the same dc current. Modulation of superconductivity and magnetic memory effects appeared only at the hybrid part of the CFs. This proves that superconductivity can be noticeably controlled under the action of the dipolar fields of FPs. The enhancement of the superconducting regime on the H-T operational diagram suggests that such hybrids can be attractive for current-carrying applications. In addition, magnetoresistive elemental superconducting devices could be based on our CFs.