Friday, March 17, 2006

SQUID Technology – Measuring Magnetism

SQUID stands for Superconducting Quantum Interference Device and is a sensitive detector for magnetic flux and it places the sensor in a cryogenic state to measure extremely small magnetic fields. Any low frequency signal that can be converted into a magnetic flux can be measured with a SQUID.

Biomedical Applications dominate the field of SQUID with companies such as Tristan Technologies, Biomagnetics Technology, CTF Systems and Neuromag leading the way in multichannel SQUID systems for imaging the brain.

SQUID technology’s history dates back to the 1970s when the company SHE (Superconducting Helium Electronics) founded by John Wheatley and his colleagues pioneered the work. This effort was followed by a cottage industry of startups in the California area. Japan entered the game and through a MITI-funded consortium pushed the technology to a new level.

Tristan Technologies is a pioneer in SQUID technology dating back to the founding days of the technology. Their applications for SQUID technology include materials analysis, biomagnetic measurements and non-destructive testing. Their noninvasive magnetic imaging system map the brain activity in infants who are at risk for cerebral palsey and epilepsy.

SQUID technology can be configured to work as a microscope for such as applications as viewing integrated circuits and ultra-thin magnetic films. It can also be used for biomagnetism. Here’s an application measuring the condition of the heart.

The Industrial Physicist one of my favorite publications, has a more detailed article on it.

Best regards,
Hall T.