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Observation of standard spin-switch effects in F/S/F trilayers with a strong ferromagnet

Ion C. Moraru·W. P. Pratt, Jr.·Norman O. Birge
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Abstract

We have measured the superconducting transition temperature T_c of F/S/F trilayers using Permalloy (Py=Ni_84 Fe_16) as a strongly polarized ferromagnetic material. For a parallel (P) or anti-parallel (AP) alignment of the magnetization directions of the outer ferromagnets, we observe a T_c difference as large as 20 mK, with a stronger suppression of superconductivity in the P state than in the AP state. This behavior is opposite to the recent observations of Rusanov et al., Phys. Rev. B 73, 060505 (2006) in Py/Nb/Py trilayers, but is consistent with earlier results on trilayers with Ni or CuNi alloy as the ferromagnetic material.

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Ion C. Moraru, W. P. Pratt, Jr., Norman O. Birge. 2006-08-24. Observation of standard spin-switch effects in F/S/F trilayers with a strong ferromagnet. https://doi.org/10.1103/physrevb.74.220507

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