Using density-functional-based methods, we show that the hole-doped Li_{ x}BC and Na_{ x}BC in P6_{ 3}/mmc crystal structure and C_{ x} in graphite structure are capable of showing superconductivity, possibly with a T_{ c} much higher than that of MgB_{ 2}. We use full-potential methods to obtain the optimized lattice constants a and c, coherent-potential approximation to describe the effects of disorder, Gaspari-Gyorffy formalism to obtain the electron-phonon coupling constant $\lambda$, and Allen-Dynes equation to calculate T_{ c} as a function of hole concentration in these alloys.
Categories: cond-mat.supr-con cond-mat.mtrl-sci