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Critical Temperature Tc and Charging Energy Ec between B-B layers of Superconducting diboride materials MgB2 in 3D JJA model

C. Kawabata·N. Hayashi·F. Ono
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Abstract

The diboride materials MB2 (M = Mg, Be, Pb, etc.) are discussed on the basis of the 3D Josephson junction array (JJA) model due to Kawabata-Shenoy-Bishop, in terms of the B-B layers in the diborides analogous to the Cu-O ones in the cuprates. We propose a possibility of superconducting materials with the MgB2-type structure which exhibit higher critical temperature Tc over 39K of MgB2. We point out a role of interstitial ionic atoms (e.g., Mg in MgB2) as capacitors between the B-B layers, which reduce the charging coupling energy in JJA.

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C. Kawabata, N. Hayashi, F. Ono. 2001-08-03. Critical Temperature Tc and Charging Energy Ec between B-B layers of Superconducting diboride materials MgB2 in 3D JJA model. https://doi.org/10.1143/jpsj.70.3184

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