Quantum spin fluctuations as a source of long-range proximity effects in diffusive ferromagnet-super conductor structures

Proximity Effects in Superconductor-Ferromagnet Structures

Singlet-triplet conversion and the long-range proximity effect in superconductor-ferromagnet structures with generic spin dependent fields.

The long-range proximity effect in superconductor-ferromagnet (S/F) hybrid nanostructures is observed if singlet Cooper pairs from the superconductor are converted into triplet pairs which can diffuse into the ferromagnet over large distances. It is commonly believed that this happens only in the presence of magnetic inhomogeneities. We show that there are other sources of the long-range triple...

Superconducting proximity effect in a diffusive ferromagnet with spin-active interfaces

We reconsider the problem of the superconducting proximity effect in a diffusive ferromagnet bounded by tunneling interfaces, using spin-dependent boundary conditions. This introduces for each interface a phaseshifting conductance G which results from the spin dependence of the phase shifts acquired by electrons upon scattering on the interface. We show that G strongly affects the density of st...

Resonant proximity effect in normal metal/diffusive ferromagnet/superconductor junctions

Resonant proximity effect in the normal metal/insulator/diffusive ferromagnet/insulator/swave and d-wave superconductor N/I/DF/I/S junctions is studied for various regimes by solving the Usadel equation with the generalized boundary conditions. Conductance of the junction and the density of states in the DF layer are calculated as a function of the insulating barrier heights at the interfaces, ...

Ferromagnetic proximity effect in a ferromagnet-quantum-dot-superconductor device.

The ferromagnetic proximity effect is studied in InAs nanowire based quantum dots strongly coupled to a ferromagnetic (F) and a superconducting (S) lead. The influence of the F lead is detected through the splitting of the spin-1/2 Kondo resonance. We show that the F lead induces a local exchange field on the quantum dot, which has varying amplitude and sign depending on the charge states. The ...