Abstract
We report superconductivity in heavily boron-doped bulk silicon carbide related to the diamond structure. The compound exhibits zero resistivity and diamagnetic susceptibility below a critical temperature Tc of ∼1.4 K, and an effective boron doping concentration higher than 1021 cm−3. We present the H–T phase diagram of this new superconducting compound determined from AC susceptibility. In finite DC magnetic fields a clear hysteresis was observed between cooling and subsequent warming runs. This indicates, in contrast with the type-II superconductivity in boron-doped diamond and silicon, that a type-I superconductivity with a critical field Hc(0) of about 100 Oe is realized in boron-doped SiC. Moreover, the specific-heat shows a clear jump at Tc, demonstrating bulk nature of the superconductivity.