SUPERCONDUCTIVITY AND MAGNETISM IN DYNI2B2C SINGLE-CRYSTALS

Superconductivity has been observed in DyNi2B2C single crystals at 6.4 K. DyNi2B2C also orders antiferromagnetically at similar to 10.5 K an d is a unique member of RNi(2)B(2)C compounds (R=Y or rare earth) in t hat the onset of superconductivity takes place in a magnetically order ed state. The crystals exhibit anomalous field-cooled magnetization in low applied fields of 1-5 Oe. Specific-heat measurements on the cryst als give further evidence for the bulk nature of the magnetic order. T he upper critical field H-c2 measured parallel and perpendicular to th e c axis of the crystals, shows little or no anisotropy. H-c2(O) for D yNi2B2C is deduced to be 0.7 T.