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Magnetization-dependent $T_c$ shift 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 Ni/Nb/Ni trilayers when the magnetizations of the two outer Ni layers are parallel (P) and antiparallel (AP). The largest difference in $T_c$ occurs when the Nb thickness is just above the critical thickness at which superconductivity disappears completely. We have observed a difference in $T_c$ between the P and AP states as large as 41 mK - a significant increase over earlier results in samples with higher $T_c$ and with a CuNi alloy in place of the Ni. Our result also demonstrates that strong elemental ferromagnets are promising candidates for future investigations of ferromagnet/superconductor heterostructures.

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Ion C. Moraru, W. P. Pratt, Jr., Norman O. Birge. 2005-12-23. Magnetization-dependent $T_c$ shift in F/S/F trilayers with a strong ferromagnet. https://doi.org/10.1103/physrevlett.96.037004

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