Thermodynamic properties of ferromagnet/superconductor/ferromagnet nanostructures -: art. no. 014523

The theoretical description of the thermodynamic properties of ferromagnet/superconductor/ferromagnet (F/S/F) systems of nanoscopic scale is proposed. Their superconducting characteristics strongly depend on the mutual orientation of the ferromagnetic layers. In addition, depending on the transparency of S/F interfaces, the superconducting critical temperature can exhibit four different types of dependences on the thickness of the F layer. The obtained results permit one to give some practical recommendations for the spin-valve effect experimental observation. In this spin-valve sandwich, we also expect a spontaneous transition from a parallel to antiparallel ferromagnetic moment orientation, due to the gain in the superconducting condensation energy.