A SQUID (Superconducting QUantum Interference Device) is a very sensitive magnetometer used to measure extremely weak magnetic fields, based on superconducting loops containing Josephson junctions.
How does it work?
SQUIDs are sensitive enough to measure fields as low as 5 aT (5×10−18 T) within a few days of averaged measurements. Their noise levels are as low as 3 fT·Hz-½. For comparison, a typical refrigerator magnet produces 0.01 tesla (10−2 T), and some processes in animals produce very small magnetic fields between 10−9 T and 10−6 T.
Biology; heart and brain Diagnosis; MRI.
Sample Handling Requirements: