Magnetic Properties Of Infinite-Layer Superconductor

Magnetic properties of n-type "infinite-layer superconductors", (Sr0.9La0.1) CuO2 prepared under high pressure were studied. From VSM and a.c. penetration measurements, the intra-grain critical current density was found to reach similar to 10(10)A/m(2) at 4.2K. Its temperature dependence as well as irreversibility field suggested that, in spite of its relatively low Tc (42K) value, the flux line lattice is rather rigid in this compound, reflecting its unique crystal structure composed only of CuO2 planes and alkali earth (rare earth) ions.