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DOE OSTI · 22922892

Characterizing the Josephson Effect on Ba-122 Single-Crystal Junctions

Reifert, D.·Schmidt, S.·Schmidl, F.·Tympel, V.·Wolf, T.
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Abstract

This paper presents c-direction hybrid Josephson junctions with base electrodes of Co:BaFe{sub 2}As{sub 2} single crystals. To realize Josephson junctions, it applies standard photolithography technologies and a newly developed surface polishing method that was used. As conventional isotropic s-wave superconductor counter electrodes used double layers of Pb/In. The artificial barrier for the tunneling junctions consists of a thin sputtered Ti layer or a thermally evaporated Al layer; both layers were used as an insulator barrier. For characterizing the Josephson effects with TiO{sub x} barrier, we could realize I{sub c}R{sub N} products of about 13.7 μV and unconventional I{sub c}-T dependencies. The formation of Shapiro steps under the influence of microwave irradiation and magnetic field to the junctions will be discussed as well.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYARSENIC COMPOUNDSBARIUM COMPOUNDSCOBALT ADDITIONSCRITICAL CURRENTDOPED MATERIALSIRON COMPOUNDSJOSEPHSON EFFECTJOSEPHSON JUNCTIONSLAYERSMAGNETIC FIELDSMICROWAVE RADIATIONMONOCRYSTALSSUPERCONDUCTORSTEMPERATURE DEPENDENCETUNNEL EFFECT

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Reifert, D., Schmidt, S., Schmidl, F., Tympel, V., Wolf, T.. 2019-09-15. Characterizing the Josephson Effect on Ba-122 Single-Crystal Junctions. https://doi.org/10.1007/s10948-019-5033-4

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