IMPROVED HIGH-FIELD PERFORMANCE OF PB1-XSNXMO6S8 RIBBONS

This paper describes the effect of Sn additions to PbMo6S 8 ribbons. These ribbons are produced via a vapor-transport technique. Small amounts of Sn in Sn1-xPbxMo 6S8 alloy ribbons provide a significant (∼10×) increase in Jc at high fields over that obtained with PbMo 6S8 alone. Critical current densities of 1×10 4 A/cm2 at 4.2 K near 20 T have been achieved for compositions with x near 0.5. The low Jc's in PbMo6S 8 appears to be related to the presence of a large fraction of a nonsuperconducting triclinic phase resulting from a partial phase transition at cryogenic temperatures. This phase transition is partially suppressed with Sn additions, resulting in an improved performance.