Abstract
We have investigated the superconducting and metallurgical properties of the ternary compounds R and R with R=Y, La, and Lu. All R compounds and were found to be type-I superconductors below 1 K. A detailed metallurgical analysis shows that segregation of second phases can easily mask the intrinsic (stoichiometric ratio 1:2:2) intermetallic-compound properties. Two sample-preparation techniques, viz., single crystals and off-stoichiometry, were utilized to establish where bulk superconductivity occurs. The type-I behavior of these compounds is explained with an analogous model as is used for the heavy-fermion superconductors and .
- Received 18 November 1985
DOI:https://doi.org/10.1103/PhysRevB.34.4566
©1986 American Physical Society