Temperature dependence and magnetic field modulation of critical currents in step-edge SNS YBCO/Au junctions

Author

Missert, N. ; Vale, L.R. ; Ono, R.H. ; Reintsema, C.D. ; Rudman, D.A. ; Thomson, R.E. ; Berkowitz, S.J.

Author_Institution

Sandia Nat. Labs., Albuquerque, NM, USA

Volume

5

Issue

2

fYear

1995

fDate

6/1/1995 12:00:00 AM

Firstpage

2969

Lastpage

2972

Abstract

We compare the electrical transport properties of superconductor-normal metal-superconductor SNS step-edge YBCO/Au junctions where the Au is deposited at 100/spl deg/C and 600/spl deg/C. For both types of junctions we observe resistively shunted junction current-voltage characteristics. The critical currents I/sub c/ in all cases are similar for a given ratio of YBCO thickness-to-step height, while the normal resistance R/sub n/ for the Au deposited at 600/spl deg/C is consistently 25% lower than for the Au deposited at 100/spl deg/C. The normalized temperature dependence of the I/sub c/R/sub n/ product is nearly identical for all junctions with Au deposited at high temperatures but varies among junctions on a single chip for Au deposited at 100/spl deg/C. Low magnetic field modulation of the critical current can show either the expected Fraunhofer-like pattern or a double-junction modulation for both types of devices. The modulation period is consistently a factor of 3 lower for the high-temperature deposited Au.<>

Keywords

Josephson effect; barium compounds; critical currents; gold; high-temperature superconductors; yttrium compounds; 100 C; 600 C; Fraunhofer pattern; YBaCuO-Au; critical currents; current-voltage characteristics; double junction; electrical transport; magnetic field modulation; normal resistance; resistively shunted junction; single chip; step-edge SNS YBCO/Au junctions; superconductor-normal metal-superconductor junctions; temperature dependence; Critical current; Current-voltage characteristics; Gold; High temperature superconductors; Josephson junctions; Magnetic fields; Magnetic modulators; Superconducting devices; Temperature dependence; Yttrium barium copper oxide;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.403215

Filename

403215