超导量子干涉仪（英语：Superconducting QUantum Interference Device），为一种极高灵敏度的磁力计，可用以探测极小磁场；其工作原理是利用包含约瑟夫森结的超导线圈。

SQUIDs 可以探测 5 aT（5×10 T）大小的磁场。 有两种基本的 SQUID: 直流 和 射频. 射频 SQUID 只需要一个约瑟夫节, 虽然灵敏度较前者低，然生产成本更低。

A SQUID (for superconducting quantum interference device) is a very sensitive magnetometer used to measure extremely subtle magnetic fields, based on superconducting loops containing Josephson junctions.

SQUIDs are sensitive enough to measure fields as low as 5 aT (5×10 T) within a few days of averaged measurements. Their noise levels are as low as 3 fT·Hz. For comparison, a typical refrigerator magnet produces 0.01 tesla (10 T), and some processes in animals produce very small magnetic fields between 10 T and 10 T. Recently invented SERF atomic magnetometers are potentially more sensitive and do not require cryogenic refrigeration but are orders of magnitude larger in size (~1 cm) and must be operated in a near-zero magnetic field.