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تسجيل مستخدم جديدSpin-valve Josephson junctions with perpendicular magnetic anisotropy for cryogenic memory
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We demonstrate a Josephson junction with a weak link containing two ferromagnets, with perpendicular magnetic anisotropy and independent switching fields in which the critical current can be set by the mutual orientation of the two layers. Such pseudospin-valve Josephson junctions are a candidate cryogenic memory in an all superconducting computational scheme. Here, we use Pt/Co/Pt/CoB/Pt as the weak link of the junction with $d_text{Co} = 0.6$ nm, $d_text{CoB} = 0.3$ nm, and $d_text{Pt} = 5$ nm and obtain a $60%$ change in the critical current for the two magnetization configurations of the pseudospin-valve. Ferromagnets with perpendicular magnetic anisotropy have advantages over magnetization in-plane systems which have been exclusively considered to this point, as in principle the magnetization and magnetic switching of layers in the junction should not affect the in-plane magnetic flux.
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Josephson junctions containing two ferromagnetic layers are being considered for use in cryogenic memory. Our group recently demonstrated that the ground-state phase difference across such a junction with carefully chosen layer thicknesses could be c
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Josephson junctions containing ferromagnetic materials have attracted intense interest both because of their unusual physical properties and because they have potential application for cryogenic memory. There are two ways to store information in such
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