A-AXIS ORIENTED YBA2CU3O7/PRBA2CU3O7 SUPERLATTICES

A modulated structure has been fabricated from high transition temperature superconductors where the individual CuO2 planes are composed of alternating superconducting and insulating strips. This structure is made by growing a-axis-oriented YBa2Cu3O7/PrBa2Cu3O7 superlattices by 90-degree off-axis sputtering on (100)SrTiO3 and (100)LaAlO3 substrates. Superlattice modulation is observed to a modulation wavelength of 24 angstroms (12 angstroms-YBa2Cu3O7/12 angstroms-PrBa2Cu3O7), both by x-ray diffraction and by cross-sectional transmission electron microscopy. Rutherford backscattering spectroscopy indicates a high degree of crystalline perfection with a channeling minimum yield of 3 percent. Quasi-one-dimensional conductivity should be obtainable in these structures.