Measuring the smallest magnets: Physicists measure magnetic interactions between single electrons

28 julio 2014

Imagine trying to measure a tennis ball that bounces wildly, every time to a distance a million times its own size. The bouncing obviously creates enormous «background noise» that interferes with the measurement. But if you attach the ball directly to a measuring device, so they bounce together, you can eliminate the noise problem. Physicists have used a similar trick to measure the interaction between the smallest possible magnets — two single electrons — after neutralizing magnetic noise that was a million times stronger than the signal they needed to detect.