Maxime Lamotte

A muon is like an electron, but 207 times heavier. When it slams into matter, it slows down like a bullet in a sandbank, and at every bend in its path it emits X-rays. Those X-rays tell you which atoms the muon encountered: that's the idea behind a technique called MIXE. It lets you peer inside an object without dismantling it, like an X-ray for materials.

The PbCuTe₂O₆ crystal resembles a three-dimensional web of copper, tellurium, and oxygen. Inside, the magnetic moments, tiny arrows tied to electron spins, are so entangled that they can't settle into an orderly arrangement even near absolute zero.