Prediction of high Tc superconductivity in hole-doped LiBC -: art. no. 127001

The layered lithium borocarbide LiBC, isovalent with and structurally similar to the superconductor MgB2, is an insulator due to the modulation within the hexagonal layers (BC vs B-2). We show that hole doping of LiBC results in Fermi surfaces of B-C psigma character that couple very strongly to B-C bond stretching modes, precisely the features that lead to superconductivity at T-c similar or equal to 40 K in MgB2. Comparison of Li0.5BC with MgB2 indicates the former to be a prime candidate for electron-phonon coupled superconductivity at substantially higher temperature than in MgB2.