University of Manchester researchers have used graphene to make some of the smallest transistors ever, at one atom thick and ten atoms wide.

They found that cutting small quantum dots of graphene gave the material switchable conductivity. Dots just a few nanometers across trap electrons due to quantum effects, and applying a magnetic field to the smallest dots lets current flow again, making a switchable transistor. The smallest dots that worked as transistors contained as few as five carbon rings–around 10 atoms or 1 nm wide.

Previous graphene transistors were significantly bigger–ribbons 10 nm across and many times longer.