Search for new superconductors in the Y-Ni-B-C system

Abstract

We have searched for superconductivity in a wide variety of stoichiometries in the Y-Ni-B-C system, using Yx(NiB)Cy phase spread alloy thin films and the magnetic field modulated microwave absorption technique. The superconducting critical temperature (Tc) varies with the stoichiometry, showing the highest Tc for a Y/Ni ratio of 1/2, attributed to the YNi2B2C phase. We found no other superconducting phases with a Tc higher than 10 K. Furthermore, a search in YxNiB(C1-zNz)y and YxNiBNy phase spread alloys showed no superconductivity. © 1997 American Institute of Physics.