Cascading Proximity Effects in Inhomogeneous Superconductor-Feromagnetic Structures

When a superconductor is placed near another material, the whole system becomes superconducting by proximity. Paired correlations with a projection on the quantization axis of zero have a shorter coherence length than those with $\pm1$ on the quantization axis. We show that the $\pm1$ projections can generate short range components deep inside a magnetic layer in the middle region of five mutually perpendicular ferromagnets as well as an exchange spring system [1,2]. Measurable consequences including the characteristic signature of short range correlations in the Josephson current of a wide layer and a new type of $0-\pi$ transition will be discussed. \\[4pt] [1] T.E. Baker, A. Richie-Halford, O.E. Icreverzi A. Bill, {\it Euro. Phys. Lett.} {\bf 107}, 17001 (2014)\\[0pt] [2] T.E. Baker, A. Richie-Halford, A. Bill, {\it New J. Phys.} {\bf 16}, 093048 (2014)