%0 Journal Article %A Ramamoorthy Ramesh %A A Inam %A W.K Chan %A B Wilkens %A K Myers %A K Remschnig %A D.L Hart %A J.M Tarascon %B Science %D 1991 %G eng %P 944-946 %R 10.1126/science.252.5008.944 %T Epitaxial cuprate superconductor/ferroelectric heterostructures %V 252 %X Thin-film heterostructures of Bi4Ti3O 12/Bi2Sr2CuO6+x have been grown on single crystals of SrTiO3, LaAlO3, and MgAl 2O4 by pulsed laser deposition. X-ray diffraction studies show the presence of c-axis orientation only; Rutherford backscattering experiments show the composition to be close to the nominal stoichiometry. The films are ferroelectric and exhibit a symmetric hysteresis loop. The remanent polarization was 1.0 microcoulomb per square centimeter, and the coercive field was 2.0 × 105 volts per centimeter. Similar results were obtained with YBa2Cu3O7-x and Bi 2Sr2CaCu2O8+x, and single-crystal Bi2Sr2CuO6+x as the bottom electrodes. These films look promising for use as novel, lattice-matched, epitaxial ferroelectronic film/electrode heterostructures in nonvolatile memory applications.