Operation of high-sensitivity radio frequency superconducting quantum interference device magnetometers with superconducting coplanar resonators at 77 K
- Institut fuer Schicht-und Ionentechnik (ISI), Forschungszentrum Juelich GmbH, D-52425 Juelich (Germany)
We have developed a novel coplanar resonator serving as a tank circuit for radio frequency washer superconducting quantum interference devices (SQUIDs). Two coplanar lines surrounded the circular flux concentrator washer, 13.4 mm in diameter. The SQUID, 3.5 mm in diameter, was coupled to the concentrator in the flip-chip configuration. All parts were fabricated from single-layer epitaxial YBa{sub 2}Cu{sub 3}O{sub 7} films on LaAlO{sub 3} substrates. In this layout, the resonant frequency could be set between 600 and 850 MHz. With SQUID loops of 100{times}100{mu}m{sup 2} (SQUID) inductance L{sub s}=150pH or 10{times}500{mu}m{sup 2} (L{sub s}=260pH), we determined at 77 K white flux noise levels S{sub {phi}}{sup 1/2} of 1.0{times}10{sup {minus}5} and 1.5{times}10{sup {minus}5}{phi}{sub 0}/{radical}(Hz), respectively. Both figures corresponded to the field resolution of about 30 fT/{radical}(Hz). {copyright} {ital 1997 American Institute of Physics.}
- OSTI ID:
- 527955
- Journal Information:
- Applied Physics Letters, Vol. 71, Issue 5; Other Information: PBD: Aug 1997
- Country of Publication:
- United States
- Language:
- English
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