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RVB Contribution to Superconductivity in $MgB_2$

G. Baskaran
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Abstract

We view $MgB_2$ as electronically equivalent to (non-staggered) graphite ($B^-$ layer) that has undergone a zero gap semiconductor to a superconductor phase transition by a large c-axis (chemical) pressure due to $Mg^{++}$ layers. Further, like the \ppi bonded planar organic molecules, graphite is an old resonating valence bond (RVB) system. The RVB's are the `preexisting cooper pairs' in the `parental' zero gap semiconducting $B^-$ (graphite) sheets that manifests themselves as a superconducting ground state of the transformed metal. Some consequences are pointed out.

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G. Baskaran. 2001-05-20. RVB Contribution to Superconductivity in $MgB_2$. https://doi.org/10.1103/physrevb.65.212505

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