Nanoscale spin ordering and spin screening effects in tunnel ferromagnetic Josephson junctions
arXiv:2503.09175 · doi:10.1038/s43246-024-00497-1
Abstract
Magnetic Josephson junctions (MJJs) have emerged as a prominent playground to explore the interplay between superconductivity and ferromagnetism. A series of fascinating experiments have revealed striking phenomena at the Superconductor/Ferromagnet (S/F) interface, pointing to tunable phase transitions and to the generation of unconventional spin-triplet correlations. Here, we show that the Josephson effect, being sensitive to phase space variation on the nanoscale, allows a direct observation of the spin polarization of the S/F interface. By measuring the temperature dependence of the Josephson magnetic field patterns of tunnel MJJs with strong and thin F-layer, we demonstrate an induced nanoscale spin order in S along the superconducting coherence length at S/F interface, i.e., the inverse proximity effect, with the first evidence of full spin screening at very low temperatures, as expected by the theory. A comprehensive phase diagram for spin nanoscale ordering regimes at S/F interfaces in MJJs has been derived in terms of the magnetic moment induced in the S-layer. Our findings contribute to drive the design and the tailoring of S/F interfaces also in view of potential applications in quantum computing.
12 pages, 5 figure, published in Communication Materials
References in corpus (24)
- Critical Current Oscillations in Strong Ferromagnetic Pi-Junctions
- Evidence for Triplet Superconductivity in a Superconductor-Ferromagnet Spin Valve
- Beyond Moore's technologies: operation principles of a superconductor alternative
- Half-integer Shapiro steps at the 0-pi crossover of a ferromagnetic Josephson junction
- Ferromagnetic Josephson switching device with high characteristic voltage
- High quality ferromagnetic 0 and pi Josephson tunnel junctions
- Inverse proximity effect in superconductor-ferromagnet bilayer structures
- Reversible control of spin-polarised supercurrents in ferromagnetic Josephson junctions
- Josephson tunnel junctions with strong ferromagnetic interlayer
- Macroscopic quantum tunneling in spin filter ferromagnetic Josephson junctions
- Theory of superconducting and magnetic proximity effect in SF structures with inhomogeneous magnetization textures and spin-active interfaces
- Macroscopic quantum dynamics of pi-junctions with ferromagnetic insulators
- Experimental Observation of the Inverse Proximity Effect in Superconductor/Ferromagnet Layered Structures
- Oscillations of Induced Magnetization in Superconductor-Ferromagnet Heterostructures
- Tuning of Magnetic Activity in Spin-Filter Josephson Junctions Towards Spin-Triplet Transport
- Magnetic-coupling-dependent spin-triplet supercurrents in helimagnet/ferromagnet Josephson junctions
- Coexistence and tuning of spin-singlet and triplet transport in spin-filter Josephson junctions
- Electrodynamics of highly spin-polarized tunnel Josephson junctions
- Spin polarization and orbital effects in superconductor-ferromagnet structures
- Supercurrent reversal in ferromagnetic hybrid nanowire Josephson junctions
- Characterization of a fabrication process for the integration of superconducting qubits and RSFQ circuits
- Inverse magnetic hysteresis of the Josephson supercurrent: study of the magnetic properties of thin niobium/permalloy (Fe_{20}Ni_{80}) interfaces
- Crossover between short and long range proximity effects in SFS junctions with Ni-based ferromagnets
- The inverse proximity effect in strong ferromagnet-superconductor structures