High Tc superconductivity at a critical strain and charge density in diborides
arXiv:cond-mat/0102410 · doi:10.1088/0953-8984/13/50/328
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).
10 pages