Low noise YBa sub 2 Cu sub 3 O sub 7 minus. delta. grain boundary junction dc SQUIDs

Journal Article · Mon Aug 13 04:00:00 EDT 1990 · Applied Physics Letters; (USA)

DOI:https://doi.org/10.1063/1.103600· OSTI ID:6516193

Gross, R; Chaudhari, P; Kawasaki, M; Ketchen, M B; Gupta, A ^[1]

---

1. IBM T. J. Watson Research Center, P. O. Box 218, Yorktown Heights, NY (USA)

We have fabricated YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} grain boundary junction dc superconducting quantum interference devices (SQUIDs) with a square washer geometry design. The SQUIDs were formed in {ital c}-axis oriented epitaxial films with a single grain boundary of predetermined nature. These SQUIDs show perfectly periodic voltage-flux characteristics without hysteresis from 4.2 to 87 K. At 77 K intrinsic energy sensitivities of 1.5{times}10{sup {minus}30} and 3.0{times}10{sup {minus}30} J/Hz at 10 kHz were obtained for 60 and 110 pH SQUIDs, respectively. The intrinsic energy sensitivity limited by 1/{ital f} noise at 10 Hz was 1.2{times}10{sup {minus}28} and 5.5{times}10{sup {minus}28} J/Hz. The SQUID voltage noise was found to be almost identical to the voltage noise from one of its junctions. The flux focusing effect of the washer geometry was also measured.

• OSTI ID: 6516193
• Journal Information: Applied Physics Letters; (USA), Journal Name: Applied Physics Letters; (USA) Vol. 57:7; ISSN APPLA; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

426001* -- Engineering-- Superconducting Devices & Circuits-- (1990-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
BARIUM OXIDES
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
CRYSTAL STRUCTURE
DESIGN
ELECTRONIC EQUIPMENT
EQUIPMENT
FABRICATION
FLUXMETERS
GRAIN BOUNDARIES
HIGH-TC SUPERCONDUCTORS
MAGNETIC FLUX
MEASURING INSTRUMENTS
MICROSTRUCTURE
MICROWAVE EQUIPMENT
OXIDES
OXYGEN COMPOUNDS
PERFORMANCE
SIGNAL-TO-NOISE RATIO
SQUID DEVICES
SUPERCONDUCTING DEVICES
SUPERCONDUCTORS
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
YTTRIUM OXIDES