TY - JOUR

T1 - Layered ferromagnet-superconductor structures

T2 - The π state and proximity effects

AU - Halterman, Klaus

AU - Valls, Oriol T.

PY - 2004/1/30

Y1 - 2004/1/30

N2 - We investigate clean mutilayered structures of the SFS and SFSFS type (where the S layer is intrinsically superconducting and the F layer is ferromagnetic), at low temperature, through numerical solution of the self-consistent Bogoliubov-de Gennes equations for these systems. We obtain results for the pair amplitude, the local density of states, and the local magnetic moment. We find that as a function of the thickness dF of the magnetic layers separating adjacent superconductors, the ground state energy varies periodically between two stable states. The first state is an ordinary “ 0 state,” in which the order parameter has a phase difference of zero between consecutive S layers, and the second is a “ π state,” where the sign alternates, corresponding to a phase difference of π between adjacent S layers. This behavior can be understood from simple arguments. The density of states and the local magnetic moment also reflect this periodicity.

AB - We investigate clean mutilayered structures of the SFS and SFSFS type (where the S layer is intrinsically superconducting and the F layer is ferromagnetic), at low temperature, through numerical solution of the self-consistent Bogoliubov-de Gennes equations for these systems. We obtain results for the pair amplitude, the local density of states, and the local magnetic moment. We find that as a function of the thickness dF of the magnetic layers separating adjacent superconductors, the ground state energy varies periodically between two stable states. The first state is an ordinary “ 0 state,” in which the order parameter has a phase difference of zero between consecutive S layers, and the second is a “ π state,” where the sign alternates, corresponding to a phase difference of π between adjacent S layers. This behavior can be understood from simple arguments. The density of states and the local magnetic moment also reflect this periodicity.

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U2 - 10.1103/PhysRevB.69.014517

DO - 10.1103/PhysRevB.69.014517

M3 - Article

AN - SCOPUS:1342280566

SN - 1098-0121

VL - 69

JO - Physical Review B - Condensed Matter and Materials Physics

JF - Physical Review B - Condensed Matter and Materials Physics

IS - 1

ER -