Low Frequency Noise in Field Cooled, High-Tc Multilayer Magnetometers
Abstract
We have studied the low frequency noise properties of high-Tc flip-chip magnetometers involving a dc Superconducting QUantum Interference Device (SQUID) coupled to a multiturn multilayer flux transformer on a separate substrate. The YBCO flux transformer consisted of an 11 x 12 mm^2 pickup loop connected to an input coil with 12 turns, each 4 μm wide. The SQUID consisted of a square washer patterned with an array of holes so that no part of YBCO film was more than 4 μm wide. The noise of the magnetometers was measured as a function of the static magnetic field in which it was cooled. The noise at 1 Hz was unchanged for cooling fields up to 68 μT, and increased rapidly for fields above 85 μT. This result shows that multilayer magnetometers can operate in the earth's magnetic field without an increase in the low frequency 1/f noise.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2000
- Bibcode:
- 2000APS..MARE12012C