 One advantage to this method is that it allows mapping of the magnetic characteristics over the surface of a sample.This can be especially useful when studying such things as the Meissner effect on superconductors.Microfabricated optically pumped magnetometers (µOPMs) can be used to detect the origin of brain seizures more precisely and generate less heat than currently available superconducting quantum interference devices, better known as SQUIDs.