New Superconducting Lead Cuprates Prepared by Molecular Beam Epitaxy

The crystal structure of superconducting copper oxides (CuO2) can be simply viewed as the stacking of two-dimensional CuO2 planes and a charge reservoir block (C.R.B.). The search for new superconductors is, in other words, the search for new charge reservoir blocks. We have succeeded in synthesizing a new superconducting cuprate PbSr2CuO5 with a pure PbO charge reservoir block using molecular beam epitaxy (MBE). This superconductor is thermodynamically quasi-stable and cannot be obtained by bulk synthesis.