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А. П. Шаповалов, С. Ю. Ларкин*, В. Е. Шатерник**, Т. А. Прихна, В. Л. Носков**, М. А. Белоголовский***
«Туннельные переходы на основе тонких плёнок MgB2 с разными функциями распределения прозрачностей »
747–758 (2011)

PACS numbers: PACS numbers: 73.40.Gk, 74.25.Sv, 74.45.+c, 74.50.+r, 74.70.Ad, 74.78.-w, 85.25.-j

Perspective Josephson Mo–Re alloy–oxide–Pb, MgB2–oxide–Mo–Re alloy, and Mo–Re alloy–normal metal–oxide–normal metal–Mo–Re alloy junctions are fabricated and investigated. Thin (??50–100 nm) Mo–Re superconducting films are deposited on Al2O3 sub-strates using dc magnetron sputtering of Mo–Re targets. Thin (??50–100 nm) MgB2 superconducting films are deposited on Al2O3 substrates using electron-beam-assisted evaporation of boron and thermal coevaporation of magnesium. To investigate trans-parency distribution of the fabricated junctions’ barriers, computer simulations of the measured quasi-particle I–V curves are performed within the scope of the model of multiple Andreev reflections in double-barrier junctions’ interfaces. As demonstrated, the investigated junctions can be described as highly asymmetric double-barrier Josephson junctions with a great difference between the two barrier transparencies [2, 3, 4]. Results of computer simulation of quasi-particles I–V curves of junctions are presented and discussed. The critical current Ic(T) characteristics measured for Josephson heterostructures with different thickness of metal layer, d, and exposure dose, E, essentially deviate from both the Ambegaokar–Baratoff (A&B) behaviour of Ic(T) and the Kulik–Omelianchuk (K&O) curves because of the proximity effect caused by the comparatively high value of d (up to 100 nm).