H. Eisaki et al., COMPETITION BETWEEN MAGNETISM AND SUPERCONDUCTIVITY IN THE NEW RARE-EARTH NICKEL BORIDE CARBIDES, Physica. C, Superconductivity, 235, 1994, pp. 2539-2540
Competition between magnetism and superconductivity was investigated f
or the newly discovered RNi(2)B(2)C superconductors with the magnetic
race earth elements R=Tm, Er, Ho, Dy, and Tb. Superconductivity is als
o observed for the compounds with magnetic R ions and their T-c's are
approximately scaled by the de Gennes factor, which implies a very wea
k coupling between the rare earth magnetic moments and the conduction
electrons due to a small conduction electron density at the rare earth
site. Associated with the antiferromagnetic order of the rare earth m
oments, characteristic resistive transition under magnetic field was o
bserved.