UC Irvine

In this paper we describe a methodology for the search for new superconducting materials. This consists of a parallel synthesis of a highly inhomogeneous alloy which covers large areas of the metallurgical phase diagram combined with a fast, microwave-based method which allows non-superconducting portions of the sample to be discarded. Once an inhomogeneous sample containing a minority phase superconductor is identified, we revert to well-known thorough identification methods which include standard physical and structural methods. We show how a systematic structural study helps in avoiding misidentification of new superconducting materials when there are indications from other methods of new discoveries. These ideas are applied to the La-Si-C system which exhibits promising normal state properties which are sometimes correlated with superconductivity. Although this system shows indications for the presence of a new superconducting compound, the careful analysis described here shows that the superconductivity in this system can be attributed to intermediate binary and single phases of the system. © 2011 IOP Publishing Ltd.