A planar gradiometer based on a microwave RF-SQUID

Author

Muck, Matthias ; Diehl, D. ; Heiden, C.

Author_Institution

Res. Centre Julich GmbH, Germany

Volume

27

Issue

2

fYear

1991

fDate

3/1/1991 12:00:00 AM

Firstpage

2983

Lastpage

2985

Abstract

A type of gradiometer, working on the basis of a planar microwave RF SQUID, is described. In this type of RF SQUID, a superconducting half-wavelength stripline resonator serves as tank circuit, into which the SQUID is integrated. If a gradiometer configuration is used for the SQUID (i.e. two loops), a certain asymmetry of the stripline resonator should be provided to ensure sufficient coupling between gradiometer and resonator. Gradiometers were prepared from thin niobium films on sapphire substrates, having either microbridges or tunnel junctions as Josephson elements. When operated in hysteretic mode, modulation voltages of about 100 μV were measured for both microbridge and tunnel junction SQUIDs

Keywords

Josephson effect; SQUIDs; magnetometers; resonators; solid-state microwave devices; strip line components; superconductive tunnelling; 100 muV; Al₂O₃; Josephson elements; Nb-Al₂O₃; coupling; hysteretic mode; microbridges; microwave RF-SQUID; modulation voltages; planar gradiometer; superconducting half-wavelength stripline resonator; tank circuit; tunnel junctions; Coils; Copper; Coupling circuits; Feedback; Frequency; Niobium; SQUIDs; Stripline; Superconducting transmission lines; Voltage;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.133837

Filename

133837