High T${}_c$ superconductivity in superhard diamond-like BC${}_5$

Abstract

Using density functional theory calculations we show that the recently-synthesized, superhard diamond-like BC${}_5$ is superconducting with a critical temperature of the same order than that of MgB${}_2$. The average electron-phonon coupling is $\hat{I}»=0.89$, the phonon-frequency logarithmic-average is $<\ddot{I}‰{>}_{\log }=67.4$ meV and the isotope coefficients are $\hat{I}\pm (C)=0.3$ and $\hat{I}\pm (B)=0.2$. In BC${}_5$, superconductivity is mostly sustained by vibrations of the B atom and its C neighbors.

4 pages, 3 figures. To appear on Phys. Rev. Lett