What does it mean to see a single atom?
Atoms are about a ten-billionth of a metre across — far too small for any light microscope. We use a scanning tunnelling microscope: an extremely sharp metal tip that moves across a surface, so close that electrons can jump between tip and sample. Measuring that tiny current point by point draws a map of the surface, atom by atom.
Tiny magnets
Electrons and atomic nuclei behave like minuscule spinning magnets, called spins. Unlike a compass needle, a spin follows the rules of quantum mechanics: it can point up and down at the same time until we measure it. That strange property is what quantum computers hope to exploit.
Graphene as a stage
Graphene is a single layer of carbon atoms arranged like a honeycomb. By building tiny pieces of graphene with atomic precision, we can decide where spins appear and how they talk to each other.
Why it matters
Learning to control individual atomic-scale magnets is a step towards new quantum technologies — and a way to answer fundamental questions about how nature works at its smallest scales.