Optimized technology for freely positionable Josephson junctions in YBa/sub 2/Cu/sub 3/O/sub 7-x/ fabricated by local ion damaging

Author

Hollkott, J. ; Jaekel, C. ; Spangenberg, B. ; Kurz, H. ; Kahlmann, F.

Author_Institution

Inst. fur Halbleitertech., Aachen, Germany

Volume

9

Issue

1

fYear

1999

fDate

3/1/1999 12:00:00 AM

Firstpage

39

Lastpage

44

Abstract

Freely positionable Josephson junctions in high-temperature superconductor thin films are fabricated by a combination of photo- and electron-beam lithography. In selected regions of YBCO thin films point defects are induced by oxygen implantation. These weak links exhibit resistively shunted junction (RSJ)-like voltage-current characteristics close to the junction transition-temperature. Below this temperature, a transition from RSJ to flux-flow behavior is observed. Fraunhofer patterns appear in magnetic modulation measurements at different temperatures. The temperature dependence of the critical current reveals superconductor/normal conductor/superconductor (SNS) features. The dependence of Shapiro steps on microwave power demonstrates Josephson contributions over the entire temperature range.

Keywords

Josephson effect; barium compounds; electron beam lithography; high-temperature superconductors; ion implantation; photolithography; superconducting thin films; yttrium compounds; Fraunhofer pattern; Josephson junction; Shapiro step; YBa/sub 2/Cu/sub 3/O/sub 7-x/; YBa/sub 2/Cu/sub 3/O/sub 7/; critical current; current-voltage characteristics; electron beam lithography; fabrication technology; flux flow; high temperature superconductor thin film; local ion damaging; magnetic modulation; microwave irradiation; oxygen implantation; photolithography; point defect; resistively shunted junction; superconductor/normal conductor/superconductor junction; transition temperature; weak link; High temperature superconductors; Josephson junctions; Lithography; Superconducting devices; Superconducting microwave devices; Superconducting thin films; Temperature dependence; Temperature measurement; Voltage; Yttrium barium copper oxide;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.763252

Filename

763252