SQUID
The game-changing scientific device you've never heard of.
(Inside Science) Meet the game-changing scientific device you've never heard of SQUID. No, not the slimy animal with tentacles that wrestles sperm whales in Moby Dick. We're talking about an entirely different kind of squid.
You can find them in machines doctors use to monitor cardiac and brain activities. You can also find them in detectors geologists use to find underground oil and silver deposits.
"So, the basic concept that we're going to be talking about is called the SQUID and that's an acronym for superconducting quantum interference device," said John Clarke from the University of California, Berkeley.
By taking advantage of a physical phenomenon known as the Josephson effect, named after physicist Brian David Josephson, who laid the theoretical groundwork for the effect in 1962, SQUIDS use a loop made of superconducting material to measure the smallest changes in a magnetic field. The result? A device that is sensitive to magnetic fields that are a thousand trillion times smaller than a typical refrigerator magnet. It’s so sensitive that it can even detect the tiniest magnetic signals from your heart or brain.
“Someone with an array of SQUIDS could tell whether or not you're actually paying attention to what I’m saying,” said Clarke.
More at this link.
https://insidescience.org/video/squid