Superconductivity at an elevated temperature in a new class of quaternary rare earth-transition metal boro-carbides

Abstract Our discovery of superconductivity at an elevated temperature (∼ 12 K) in the system YNiBC has opened up an entirely new area of research in superconductivity of intermetallics. We briefly present the results of our recent studies on magnetic history effects in YNi 2 B 2 C, the coexistence of superconductivity and magnetism in ErNi 2 B 2 C, the effect of substituents on superconductivity in YNi 2 B 2 C, the mixed valence of Ce in CeNi 2 B 2 C and superconductivity in Th-based borocarbides.