Title :
A single-chip SQUID magnetometer
Author :
Fujimaki, Norio ; Tamura, Hirotaka ; Imamura, Takeshi ; Hasuo, Shinya
Author_Institution :
Fujitsu Lab. Ltd., Atsugi, Japan
fDate :
12/1/1988 12:00:00 AM
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/AlOx/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-AlOx-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;
Journal_Title :
Electron Devices, IEEE Transactions on
