Effect of Tb substitution for Dy on superconductivity and magnetism in Dy1-xTbxNi2B2C

Abstract

The superconductivity and the magnetism of Dy1-xTbxNi2B2C (0.0 <= x <= 1.0) single crystals were studied. As Tb+3 was substituted for Dy+3, the superconducting transition temperature T-c decreased linearly at a rate of dT(c)/dx=-12 K, and for x >= 0.4, no superconductivity was observed above 2 K. In contrast, the antiferromagnetic ordering temperature T-N was almost constant for x <= 0.6. These behaviors are in sharp contrast to the case of Dy1-xHoxNi2B2C, where the T-c is constant for x > 0.7 but the T-N decreases linearly with x. The difference between Dy1-xTbxNi2B2C and Dy1-xHoxNi2B2C can be understood if the magnetic structures of both compounds are properly considered.