Physical properties of Lu1xYbxNi2B2C
- Additional Document Info
- View All
The Lu 1-xYb xNi 2B 2C system exhibits superconductivity at low Yb concentrations (0 x 0.1), Kondo behaviour at low and moderate Yb concentrations (0 x 0.34), and heavy fermion behaviour with a non-magnetic ground state at high Yb concentrations. In order to characterize the evolution of these phenomena with x , we have performed dc magnetic susceptibility, electrical resistivity, thermoelectric power, and specific heat measurements on single crystals of Lu 1- x Yb x Ni 2 B 2 with various values of x between 0 and 1. The enhanced suppression of T c by Yb substitution, compared to other rare earth substitutions, is consistent with the behaviour of superconducting Kondo systems with T K T c when T K decreases with increasing x . The electronic specific heat coefficient increases from 11 mJ/mol K 2 for x =0 to 530 mJ/mol K 2 for x =1. The curve of the reduced specific heat jump C / C 0 versus T c / T c0 , where C 0 and T c0 refer to the LuNi 2 B 2 C matrix, does not conform to the BCS theory, but is consistent with the magnetic pair breaking theory of Abrikosov and Gor'kov or the theory of Mller-Hartmann and Zittartz for superconductivity in the presence of the Kondo effect for . This is in agreement with the evolution of the upper critical field H c2 with x , where the slope decreases with increasing x.
author list (cited authors)
Li, S., De Andrade, M. C., Freeman, E. J., Sirvent, C., Dickey, R. P., Amann, A., ... Maple, M. B.
complete list of authors
Li, S||De Andrade, MC||Freeman, EJ||Sirvent, C||Dickey, RP||Amann, A||Frederick, NA||Rathnayaka, KDD||Naugle, DG||Bud’ko, SL||Canfield, PC||Beyermann, WP||Maple, MB