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The Tc amplification by quantum interference effects in diborides

Annette Bussmann-Holder·Antonio Bianconi
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Abstract

The model of two (s and p) channel superconductivity known to be necessary to explain the superconductivity in MgB2 has been applied to the Al1-xMgxB2 diborides by tuning x from MgB2 to AlMgB4. The evolution of the interband coupling parameter (probing the strength of the interchannel pairing due to quantum interference effects) and the two gaps in the s and p channel as a function of x have been calculated. While in MgB2 the quantum interference effects give an amplification of Tc by a factor of 1.5 in comparison with the dominant intra s band single channel pairing, in AlMgB4 the amplification is about 100, in comparison with the dominant intra p band single channel pairing.

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Annette Bussmann-Holder, Antonio Bianconi. 2002-11-18. The Tc amplification by quantum interference effects in diborides. https://doi.org/10.1103/physrevb.67.132509

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