Observation of the dominant spin-triplet supercurrent in Josephson spin valves with strong Ni ferromagnets

Abstract

We study experimentally nanoscale Josephson junctions and Josephson spin-valves containing strong Ni ferromagnets. We observe that in contrast to junctions, spin valves with the same geometry exhibit anomalous Ic(H) patterns with two peaks separated by a dip. We develop several techniques for in-situ characterization of micromagnetic states in our nano-devices, including magnetoresistance, absolute Josephson fluxometry and First-Order-Reversal-Curves analysis. They reveal a clear correlation of the dip in supercurrent with the antiparallel state of a spin-valve and the peaks with two noncollinear magnetic states, thus providing evidence for generation of spin-triplet superconductivity. A quantitative analysis brings us to a conclusion that the triplet current in out Ni-based spin-valves is approximately three times larger than the conventional singlet supercurrent.

10 pages, 7 Figures

References in corpus (6)

• Superconducting triplet spin valve
• Reversible control of spin-polarised supercurrents in ferromagnetic Josephson junctions
• Controllable generation of a spin-triplet supercurrent in a Josephson spin-valve
• Evidence for spin-triplet superconducting correlations in metal-oxide heterostructures with non-collinear magnetization
• Magnetic anisotropy in ferromagnetic Josephson junctions
• Accessing Different Spin-Disordered States using First Order Reversal Curves

Cited by in corpus (4)

• Magnetization dynamics in proximity-coupled superconductor/ferromagnet/superconductor multilayers
• Crossover between short and long range proximity effects in SFS junctions with Ni-based ferromagnets
• Supergap and subgap enhanced currents in asymmetric {S_1FS_2} Josephson junctions
• In situ transport characterization of magnetic states in Nb/Co superconductor/ferromagnet heterostructures