The crystal CeB6 is like a box with a secret: inside it, electrons can occupy four nearly identical positions, like four chairs around a table. While no one is watching, the electron seems to sit on all four at once. Physicists call this hidden state quadrupolar, and it affects magnetic properties, but it is hard to see directly.
Scientists have found a way to make such a crystal 'speak.' They simultaneously send into it a sound wave (ordinary pressure, like gently pressing on the lid of the box) and microwave radiation. Together they act like two keys that must be turned at the same time. The electron in the hidden state absorbs a particle of sound and a particle of light at once, and by how the signal changes, one can tell exactly where it was hiding.
This approach opens the door to studying other materials where electrons behave secretly. Previously, there wasn't enough energy for this, but now sound and microwaves together do the impossible.
Quadrupolar states are like four identical chairs: the electron doesn't pick one but sits on all at once until disturbed.