Superconductivity paramagnetic impurities

Craven et al. (1971) have shown the influence of dilute erbium impurities (0.274 to 0.006 at%) on the superconducting transition of aluminum thin films, overlayered by SiO. They have observed that the anomalous excess conductivity in Al films is quenched by the addition of paramagnetic impurities. The transition temperature varied from 1.575 to 1.95 K, but non-linearly with the Er content. 

Here we will concentrate on lanthanide systems which built up well-localized moments. In the class of dilute lanthanide metals and intermetallic compounds for which spin-glass behavior has been reported, one topic involves 4f-impurities in superconducting hosts. Already a small amount of paramagnetic impurities, as... 

Section 4 presents some selected topics on superconducting rare earth alloys and compounds. In this chapter we do not discuss the influence of paramagnetic rare earth impurities on the Tc of a superconducting host metal. There is an excellent recent review of this subject by Maple (1973). The chapters by Fulde and Maple will also cover this topic. Finally, section 5 summarizes our conclusions. 

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