Performances of compact integrated superconducting magnetometers for biomagnetic imaging

In the present paper, performances of compact fully integrated superconducting quantum interference device (SQUID) magnetometers, recently developed, have been investigated in view of their employment in large multichannel systems for biomagnetic imaging. The analysis has been focused on SQUID sensors having a pickup loop side length of 3 and 4 mm based on a design aimed to maximize the magnetic flux transferred from the detection coil to the SQUID in comparison with a magnetometer with 9 mm side length having a suitable sensitivity for biomagnetic applications. The performance study has been consisted in the computation of the magnetic responses to a current dipole which is the most fundamental approach used in biomagnetism. The results have shown that the dipole current sensitivity of 4 mm long side compact magnetometers is suitable for application in multichannel systems for magnetoencephalography and magnetocardiography.