Compensation System for Biomagnetic Measurements with Optically Pumped Magnetometers inside a Magnetically Shielded Room
Anna Jodko-Władzińska , Krzysztof Wildner , Tadeusz Pałko , Michał Władziński
AbstractMagnetography with superconducting quantum interference device (SQUID) sensor arrays is a well-established technique for measuring subtle magnetic fields generated by physiological phenomena in the human body. Unfortunately, the SQUID-based systems have some limitations related to the need to cool them down with liquid helium. The room-temperature alternatives for SQUIDs are optically pumped magnetometers (OPM) operating in spin exchange relaxation-free (SERF) regime, which require a very low ambient magnetic field. The most common two-layer magnetically shielded rooms (MSR) with residual magnetic field of 50 nT may not be sufficiently magnetically attenuated and additional compensation of external magnetic field is required. A cost-efficient compensation system based on square Helmholtz coils was designed and successfully used for preliminary measurements with commercially available zero-field OPM. The presented setup can reduce the static ambient magnetic field inside a magnetically shielded room, which improves the usability of OPMs by providing a proper environment for them to operate, independent of initial conditions in MSR.
|Journal series||Sensors, [SENSORS-BASEL], ISSN 1424-8220, e-ISSN 1424-3210|
|Publication size in sheets||0.65|
|Keywords in English||optically pumped magnetometer, magnetically shielded room, Helmholtz coils, biomagnetism|
|ASJC Classification||; ; ;|
|License||Journal (articles only); published final; ; after publication|
|Score||= 100.0, 02-09-2020, ArticleFromJournal|
|Publication indicators||: 2016 = 1.393; : 2018 = 3.031 (2) - 2018=3.302 (5)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.