Dc-SQUID magnetometers and gradiometers on the basis of quasiplanar ramp-type Josephson junctions

Author

Faley, M.I. ; Poppe, U. ; Urban, K. ; Krause, H.-J. ; Soltner, H. ; Hohmann, R. ; Lomparski, D. ; Kutzner, R. ; Wordenweber, R. ; Bousack, H. ; Braginski, A.I. ; Slobodchikov, V.Yu. ; Gapelyuk, A.V. ; Khanin, V.V. ; Maslennikov, Yu.V.

Author_Institution

Inst. fur Festkorperforschung, Forschungszentrum Julich GmbH, Germany

Volume

7

Issue

2

fYear

1997

fDate

6/1/1997 12:00:00 AM

Firstpage

3702

Lastpage

3705

Abstract

Nonaqueous Br-ethanol chemical etching was successfully used for the preparation of the Josephson junctions, vias and crossovers in magnetometers including flux transformers. PrBa/sub 2/Cu/sub 3/O/sub 7-x/ thin films were used for the barrier layer in the Josephson junctions of the SQUIDs and as an insulation in the junctions and in the flux transformers. Dc-SQUID magnetometers with small inductances and even without flux antennas were used for NDE applications which mainly require a high dynamic range. Highly sensitive devices were prepared with flip-chip flux antennas. An ac-bias SQUID electronics significantly improves the sensitivity of the magnetometers at low frequencies.

Keywords

Josephson effect; SQUID magnetometers; etching; high-temperature superconductors; DC-SQUID magnetometer; NDE; PrBa/sub 2/Cu/sub 3/O/sub 7-x/ thin film; PrBa/sub 2/Cu/sub 3/O/sub 7/; barrier layer; crossover; dynamic range; fabrication; flip-chip flux antenna; flux transformer; gradiometer; inductance; insulation; nonaqueous Br-ethanol chemical etching; quasiplanar ramp-type Josephson junction; via; Chemicals; Critical current density; Electrodes; Etching; Josephson junctions; Magnetic shielding; Power transformer insulation; SQUID magnetometers; Temperature sensors; Transistors;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.622222

Filename

622222