Superconducting T′-La2-xCexCuO4 films grown by molecular beam epitaxy

We report the synthesis of superconducting T ' -La2-xCexCuO4 on SrTiO3(0 0 1) by molecular beam epitaxy. Although T ' -La2-xCexCuO4 with a very limited range of x can be prepared by bulk synthesis using rather complicated techniques. this compound is very easy to obtain by thin film synthesis. The best Tc was above 30 K at onset and similar to 29.5 K at zero resistance, which was obtained for x = 0.11. These values are the highest among electron-doped T ' superconductors. Moreover, the single-phase T ' structure is formed for a composition range of 0.09 < x < similar to0.4, which is much wider than for previously reported bulk synthesis (C) 2001 Elsevier Science B.V. All rights reserved.