Daniel C. Ralph

Using a method similar to spectroscopy (magnetic sensing), scientists pass a current through a multilayer film and observe the orientation of the microscopic magnetic arrows inside. Previously, everything was predictable: in some materials, the arrows aligned only along the current, in others — strictly across it. But in bismuth ferrite with a platinum coating, a glitch occurred.

The edge of a magnet works like a guitar fret: a string pressed near the edge sounds different, with a richer set of overtones. Magnetic waves in a thin strip of nickel and iron behave in much the same way.