Magnetic switches based on Nb-PdFe-Nb Josephson junctions with a magnetically soft ferromagnetic interlayer

The properties of Josephson junctions with a barrier made of a PdFe weakly ferromagnetic alloy with an iron content of about 1 at % have been studied. It has been shown that this alloy is a weak ferromagnet with a Curie temperature of 10–15 K in the required thickness range of 30–50 nm. The effect of the domain structure and magnetic prehistory of the ferromagnetic barrier on the critical current of a junction and the form of the Josephson characteristics has been demonstrated. The application of these junctions as magnetic switches has been proposed.

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