Growth and transport properties of Y-Ba-Cu-O/Pr-Ba-Cu-O superlattices

Conference · Mon Jan 01 04:00:00 EST 1990

OSTI ID:6534251

Lowndes, D H; Norton, D P; Budai, J D; Christen, D K; Klabunde, C E; Warmack, R J; Pennycook, S J

The pulsed-laser deposition method has been used to fabricate epitaxial, nonsymmetric M(Y) {times} N(Pr) superlattices in which YBa{sub 2}Cu{sub 3}O{sub 7-x} (YBCO) layers either M = 1,2,3,4,8, or 16 c-axis unit cells thick are separated by insulating PrBa{sub 2}Cu{sub 3}O{sub 7-x} (PBCO) layers N unit cells thick (N = 1 to {approximately}32). The zero-resistance superconducting transition temperature, T{sub c0}, initially decreases rapidly with increasing PBCO layer thickness, but then saturates at T{sub c0} {approximately} 19 K, 54 K, 71 K, or 80 K, or structures containing 1-,2-,3-, or 4-cell-thick YBCO layers, respectively. Critical current density measurements carried out on structures with 16- or 32-cell thick YBCO layers show that the magnitude of J{sub c}(H = 0) {approximately} 1-2 MA/cm{sup 2}, as well as the magnetic field dependence and the anisotropy of J{sub c}(H) all are in good agreement with corresponding measurements on thicker, single-layer YBCO films. Thus, there is no evidence of an enhanced J{sub c}(H) due to the multi-layered structure, for the layer thickness investigated to date. The systematic variation of T{sub c0}, as a function of the YBCO and PBCO layer thickness, is discussed in light of other recent experiments and theoretical model calculations. The superlattices' structural and compositional order are characterized using x-ray diffraction, transmission electron microscopy, and scanning tunneling microscopy, and details of the pulsed-laser deposition process are reported. 42 refs., 7 figs.

• Research Organization: Oak Ridge National Lab., TN (USA)
• Sponsoring Organization: DOE/ER
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6534251
• Report Number(s): CONF-9009173-1; ON: DE91000721
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201 -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
ABLATION
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
BARIUM OXIDES
CHALCOGENIDES
COHERENT SCATTERING
COPPER COMPOUNDS
COPPER OXIDES
CRITICAL CURRENT
CURRENT DENSITY
CURRENTS
DEPOSITION
DIFFRACTION
ELECTRIC CURRENTS
ELECTRICAL PROPERTIES
HIGH-TC SUPERCONDUCTORS
MAGNETIC FIELDS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
PRASEODYMIUM COMPOUNDS
PRASEODYMIUM OXIDES
RARE EARTH COMPOUNDS
SCATTERING
SUPERCONDUCTORS
SUPERLATTICES
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE
X-RAY DIFFRACTION
YTTRIUM COMPOUNDS
YTTRIUM OXIDES