Magnetic sensors are used across a range of applications and industries, including the medical, oil prospecting, defense and security sectors.
Their most well-known use is perhaps in medical imaging technology including MRI scanners – used to diagnose a range of conditions, plan treatments and assess the effectiveness of previous therapies.
The sensors rely on a superconducting quantum interference device (SQUID) that converts magnetic flux – a measure of magnetic intensity – into a voltage that can then be read.
Currently, the most sensitive commercial magnetic sensors make use of a single SQUID which must be kept at 4.2 Kelvin (-268.95 ºC).
This super-cold temperature is usually maintained using liquid helium which is both expensive and difficult to handle.
Alternative SQUIDs – that can operate at higher temperatures and are cooled by the more cost-effective and less intractable liquid nitrogen – are available, but are less sensitive.
Researchers at Loughborough University have addressed this issue and devised a viable and effective solution that could revolutionise SQUID technology.