Proximity Effect as a Probe of Electronic Correlations and Exchange Field in Dirty Ferromagnet/Superconductor Nanostructures
We investigate the interplay between the BCS and 2D Larkin-Ovchinnikov-Fulde-Ferrell (LOFF) states in the dirty thin ferromagnetic metal/superconductor (FM/S) nanostructures. For the FM/S bilayers we have derived the dependencies of critical temperature on the FM layer exchange field, electronic correlations and thickness. Moreover, in the corresponding FM/S/FM trilayers we predict two new π phase superconducting states with electron-electron repulsion in the FM layers. The 2D modulated LOFF states are possible in such trilayers only in presence of a weak magnetic field and at suitable parameters of the FM and S layers. On this base we originally propose the method of proximity effect probe the magnitude and sign of the electronic correlations, the order parameter symmetry and exchange fields in various FM layers.
L. A. Terentieva et al., "Proximity Effect as a Probe of Electronic Correlations and Exchange Field in Dirty Ferromagnet/Superconductor Nanostructures", Solid State Phenomena, Vols. 152-153, pp. 457-461, 2009