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J.-M. Triscone, <178>. Fischer, O. Brunner, L. Antognazza, A.D. Kent, "YBa2Cu3O7/PrBa2Cu3O7 superlattices: Properties of ultrathin superconducting layers separated by insulating layers," Physical Review Letters, 64:804-7, 1990.
J.-M. Triscone (currently at Stanford University, Calif.): "I think the realization of YBa2Cu3O7/PrBa2Cu3O7 (and YBa2Cu3O7/DyBa2Cu3O7) superlattices had a strong impact because it demonstrated that high-quality epitaxial heterostructures can be made with sharp (one unit cell) interfaces. This was accomplished in spite of the complex structure of high Tc superconductors (HTS), and the extreme conditions required to form the phase in situ. Such heterostructures--typically, superconductor/insulator (or normal metal) artificial structures--are essential to realize any useful device. PrBa2Cu3O7, being isostructural to YBa2Cu3O7 but not superconducting, is an interesting candidate for such structures, although it is not an ideal insulator. After this work, several groups in the United States, Europe, and Japan have realized artificial structures using YBa2Cu3O7, PrBa2Cu3O7 or other oxide combinations. Our superlattices also...