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MgB2 tunnel junctions with native or thermal oxide barriers

R. K. Singh·R. Gandikota·J. Kim·N. Newman·J. M. Rowell
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Abstract

MgB2 tunnel junctions (MgB2/barrier/MgB2) were fabricated using a native oxide grown on the bottom MgB2 film as the tunnel barrier. Such barriers therefore survive the deposition of the second electrode at 300oC, even over junction areas of ~1 mm2. Studies of such junctions, and those of the type MgB2/native or thermal oxide/metal (Pb, Au, or Ag) show that tunnel barriers grown on MgB2 exhibit a wide range of barrier heights and widths.

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R. K. Singh, R. Gandikota, J. Kim, N. Newman, J. M. Rowell. 2006-04-09. MgB2 tunnel junctions with native or thermal oxide barriers. https://doi.org/10.1063/1.2226546

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