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High Tc superconductivity at a critical strain and charge density in diborides

A. Bianconi·N. L. Saini·D. Di Castro·S. Agrestini·G. Campi·A. Saccone·S. De Negri·M. Giovannini M. Colapietro
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Abstract

We report variation of lattice structure in diborides (AB2) with different A atoms to identify the special case of MgB2 showing high Tc superconductivity. High purity MgB2 (Tc~39 K) has been prepared by direct reaction of the elements and the lattice parameters are measured by x-ray diffraction determining the strain e of the B-B distance. The results show that the superconductivity in these intermetallics appear near a critical point in a two variables (strain and charge density) phase diagram at (ec, rc).

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A. Bianconi, N. L. Saini, D. Di Castro, S. Agrestini, G. Campi, A. Saccone, S. De Negri, M. Giovannini M. Colapietro. 2001-11-20. High Tc superconductivity at a critical strain and charge density in diborides. https://doi.org/10.1088/0953-8984%2F13%2F50%2F328

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