Finding zero, simply: Adelaide engineers give the world's most sensitive magnetic sensors a clever loop trick

Some instruments can sense magnetic fields so faint they can help doctors picture the living brain. The best of them, called SQUIDs, have one awkward flaw: to work at full sharpness they struggle to tell when a field is exactly zero, and the usual fix — building circuits from hundreds of loops of different sizes — dulls the very sensitivity that makes them special. Adelaide University engineers led by Associate Professor Giuseppe Tettamanzi found a plainer answer: keep every loop the same size, but leave a few of them bare, with no key component inside. In tests published in Physical Review Applied, the simpler circuits behaved exactly as predicted — full sensitivity, zero found, and a design that should be cheaper and easier to make.

SDG 9 · Industry, innovation and infrastructure — Mechanism: tech innovation