Non-local current correlations in ferromagnet/superconductor nanojunctions
Absztrakt:
When two fully polarized ferromagnetic (F) wires with opposite
polarizations make contact with a spin-singlet superconductor, a
potential-induced current in wire 1 induces a non-local current
of equal magnitude and sign in wire 2. The magnitude of this
current has been studied in the tunneling limit and found to
decay exponentially with the distance between the contact. In
this paper we propose a new structure in which this novel non-
local effect is increased by orders of magnitude. We study the
spin-dependent electronic transport of a diffusive nanojunction
and demonstrate that when a normal diffusive region is placed
between the F leads and superconductor, the non-local initially
increases with the separation between the F leads, achieving a
maximum and decays as a power law with increasing separation.