In the field of national defense, magnetic detection technology is mainly used to detect hidden metal targets, such as submarines, underwater mines, ground tanks, shells, etc. The current traditional methods include sonar, radar, and magnetic anomaly detection. In terms of magnetic anomaly detection, anti submarine aircraft are often equipped with magnetic detector (MAD) pods, which usually use high-sensitivity flux gates or optical pump magnetometers to detect the disturbance of submarine steel

Magnetic measurements are widely used in the field of geophysical exploration to explore underground ore bodies, geological structures, and geomagnetic anomalies. At present, mainstream magnetic sensing technologies include flux gates (three-axis vector measurement, sensitivity generally at nT level), proton precession magnetometers (scalar measurement, high stability but large volume, low sampling rate), Overhauser and cesium vapor optically pumped magnetometers (scalar, high sensitivity), etc.

Currently, magnetoencephalography (MEG) and magnetocardiography (MCG) mainly rely on superconducting quantum interferometers (SQUID) magnetometers to measure the extremely weak magnetic field signals generated by the brain and heart. Although the SQUID sensor has extremely high sensitivity, it must be immersed in liquid helium to maintain a low temperature of about 4 K and fixedly installed in a rigid helmet array, maintaining a distance of about 2 centimeters from the scalp.

Magnetic testing is one of the important methods in industrial non-destructive testing (NDT). For example, faults such as short circuits in the windings of motors and generators, demagnetization of magnetic steel, etc. can cause abnormal distribution of external magnetic fields. Detecting the magnetic field around the running motor can detect potential faults early and avoid major shutdown accidents. Traditional methods mainly rely on vibration noise analysis and electrical parameter testing

In basic scientific research, highly sensitive magnetic instruments are powerful tools for exploring new scientific phenomena. For example, in neuroscience experiments, researchers hope to measure the subtle magnetic fields of animal or human brain neural activity in real time to study the principles of brain function. Such experiments often require more flexible sensor arrangements and higher spatiotemporal resolution than clinical MEG.

Magnetometers are commonly used attitude and environmental sensing sensors on spacecraft. On the one hand, scientific satellites require high-precision measurement of the Earth's magnetic field to draw geomagnetic maps and monitor space weather; For example, the Swarm constellation of the European Space Agency is equipped with high-precision magnetometers for modeling the geomagnetic field.