Producing superconductors by epitaxial growth

摘要

Superconductors having a superconductive layer deposited by liquid phase epitaxy (LPE) are described. Examples have substrate of Ni bearing (1) a seed layer of NiO formed by surface oxidation epitaxy upon which are deposited, by LPE, a further NiO layer and a buffer layer of Nd2CuO4 or (2) a vapour deposited buffer layer of Pt or Pd alloy. In each case a conventional REBCO layer is then deposited by LPE. A method of LPE coating involves feeding a rod of superconductor and flux (eg RE2CuO4 with CuO) downwards into the focus of a laser to produce a melt which is allowed to fall onto a moving and suitably textured substrate (eg as described above) which is at a temperature lower than the melt, whereby epitaxial growth is promoted.