Properties of YBaCuO nanobridges and dc-SQUIDs

Author

Pedyash, M.V. ; Blank, D.H.A. ; de Muijnck, J.H. ; Rogalla, H.

Author_Institution

Dept. of Appl. Phys., Twente Univ., Enschede, Netherlands

Volume

7

Issue

2

fYear

1997

fDate

6/1/1997 12:00:00 AM

Firstpage

2764

Lastpage

2767

Abstract

YBaCuO nanobridges and inductively shunted dc-SQUIDs have been patterned by direct Focused Ion Beam milling. Nanobridges manifest true Josephson effect, which can be explained by coherent motion of Abrikosov vortices in the bridge. An enhancement of this effect is proposed to be due to local suppression of the superconducting properties within the nanobridge area. This leads to a transition from SNS to SS´S type behavior of the nanobridge with decreasing temperature. Temperature dependence of the critical current, dynamic resistance, and SQUID voltage-flux modulation is discussed. The flux noise level of the nanoSQUID is measured to be about 6.5 /spl mu//spl Phi//sub 0///spl radic/Hz at 62.7 K.

Keywords

Josephson effect; SQUIDs; barium compounds; critical current density (superconductivity); focused ion beam technology; high-temperature superconductors; nanotechnology; superconducting device testing; superconducting microbridges; superconducting thin films; yttrium compounds; 62.7 K; Abrikosov vortices; SS´S type behavior; YBaCuO; coherent motion; critical current; direct focused ion beam milling; dynamic resistance; flux noise level; inductively shunted dc-SQUIDs; local suppression; nanoSQUID; nanobridges; true Josephson effect; voltage-flux modulation; Bridge circuits; Critical current; Ion beams; Josephson effect; Milling; Superconducting device noise; Superconducting devices; Superconducting transition temperature; Temperature dependence; Yttrium barium copper oxide;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.621810

Filename

621810