Proximity-driven source of highly spin-polarized ac current on the basis of superconductor/weak ferromagnet/superconductor voltage-biased Josephson junction
A. M. Bobkov, I. V. Bobkova
Institute of Solid State Physics RAS, 142432 Chernogolovka, Moscow reg., Russia
PACS: 74.45.+c, 74.50.+r
Abstract
We theoretically investigate an opportunity to implement
a source of highly spin-polarized ac current on the basis of
superconductor/weak ferromagnet/superconductor (SFS)
voltage-biased junction in the regime of essential proximity
effect and calculate the current flowing through the probe
electrode tunnel coupled to the ferromagnetic interlayer region.
It is shown that while the polarization of the dc current
component is generally small in case of weak exchange field of the
ferromagnet, there is an ac component of the current in the
system. This ac current is highly spin-polarized and entirely
originated from the non-equilibrium proximity effect in the
interlayer. The frequency of the current is controlled by the
voltage applied to SFS junction. We discuss a possibility to
obtain a source of coherent ac currents with a certain phase shift
between them by tunnel coupling two probe electrodes at different
locations of the interlayer region.