A single-chip SQUID magnetometer

Author

Fujimaki, Norio ; Tamura, Hirotaka ; Imamura, Takeshi ; Hasuo, Shinya

Author_Institution

Fujitsu Lab. Ltd., Atsugi, Japan

Volume

35

Issue

12

fYear

1988

fDate

12/1/1988 12:00:00 AM

Firstpage

2412

Lastpage

2418

Abstract

A superconducting quantum interference device (SQUID) magnetometer in which all components are integrated on a single chip is discussed. The chip includes a feedback circuit, a pickup coil, and a SQUID sensor. The feedback circuit consists of a superconducting storage loop and a WRITE gate. The chip, fabricated with Nb/AlO_x/Nb Josephson junctions, Mo resistors and SiO₂ insulation. The sensitivity is 7×10^-5 Φ₀/√Hz for the flux in the SQUID sensor and 4.5×10^-9 T/m √Hz for the magnetic field gradient at the pickup coil. This sensitivity is limited by environmental noise and can be increased with shielding. The device is useful for the construction of a magnetometer array for biomagnetic image sensing

Keywords

SQUIDs; magnetometers; thin film circuits; Josephson junctions; Mo resistors; Nb-AlO_x-Nb junctions; SQUID sensor; SiO₂ insulation; WRITE gate; biomagnetic image sensing; environmental noise; feedback circuit; magnetometer array; pickup coil; shielding; single-chip SQUID magnetometer; superconducting quantum interference device; superconducting storage loop; Feedback circuits; Insulation; Interference; Josephson junctions; Magnetic sensors; Niobium; Resistors; SQUID magnetometers; Superconducting coils; Superconducting devices;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/16.8823

Filename

8823