Superconductivity in RNi2B2C (R = rare earth) compounds

Abstract A series of compounds in the recently discovered RNi 2 B 2 C family of superconductors have been prepared in order to investigate their magnetic and transport properties. Compounds of the form (Y 1−x A x )Ni 2 B 2 C (A=Sm,Dy) were examined to study the effects of magnetic pair breaking. Resistance measurements show that the lighter rare earth Sm depresses T c faster than the heavier rare earth Dy. Solid solutions of the type (Er 1−x Ho x )Ni 2 B 2 C have also been studied for the possible coexistence of superconductivity and magnetism in these compounds. Even though the magnetic ordering of the rare earth moments can be deduced from our susceptibility measurements, resistance measurements showed no reetrant behavior in any of these compounds down to 1.2 K.