Focused ion beam fabrication of single grain Bi sub 2 Sr sub 2 Ca sub 1 Cu sub 2 O sub x submicron bridges

Journal Article · Mon Aug 05 00:00:00 EDT 1991 · Applied Physics Letters; (United States)

DOI:https://doi.org/10.1063/1.105353· OSTI ID:5482706

Zitkovsky, I D; Hu, Q; Orlando, T P; Melngailis, J; Tao, T ^[1]

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1. Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts (USA)

Superconducting microbridges have been patterned by direct milling of the Bi{sub 2}Sr{sub 2}Ca{sub 1}Cu{sub 2}O{sub {ital x}} polycrystalline thin films using focused ion beam. Several single grain and multigrain bridges of sizes as small as 0.3 {mu}m have been fabricated. Single grain microbridges exhibit a linear temperature dependence of the critical current density with {ital J}{sub {ital c}}=10{sup 6} A/cm{sup 2} at 8 K, and zero magnetic field. Larger 50--100 {mu}m bridges show lower critical current densities of {ital J}{sub {ital c}}=10{sup 4}--10{sup 5} A/cm{sup 2}. The current-voltage ({ital I}-{ital V}) and the {ital J}{sub {ital c}} vs {ital T} characteristics show two qualitatively different types of superconducting weak links. The single grain microbridges behave as homogeneous superconductors with transport exhibiting flux creep and flux flow. The large bridges can be characterized as granular superconductors with weakly connected grains, and their {ital I}-{ital V} and the {ital J}{sub {ital c}} vs {ital T} characteristics are dependent on processing conditions.

• OSTI ID: 5482706
• Journal Information: Applied Physics Letters; (United States), Vol. 59:6; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
36 MATERIALS SCIENCE
SUPERCONDUCTING JUNCTIONS
CRITICAL CURRENT
FABRICATION
BISMUTH OXIDES
CALCIUM OXIDES
COPPER OXIDES
ION BEAMS
MAGNETIC FLUX
STRONTIUM OXIDES
SUPERCONDUCTING FILMS
TEMPERATURE DEPENDENCE
ALKALINE EARTH METAL COMPOUNDS
BEAMS
BISMUTH COMPOUNDS
CALCIUM COMPOUNDS
CHALCOGENIDES
COPPER COMPOUNDS
CURRENTS
ELECTRIC CURRENTS
FILMS
JUNCTIONS
OXIDES
OXYGEN COMPOUNDS
STRONTIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
426001* - Engineering- Superconducting Devices & Circuits- (1990-)
360204 - Ceramics
Cermets
& Refractories- Physical Properties