Title :
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
fDate :
6/1/1997 12:00:00 AM
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;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
