Size gives light its colour

01 / WHAT CHANGES

The mechanism

When a semiconductor nanocrystal confines charge carriers within sufficiently small dimensions, the available electronic states change. Within the same family of materials, smaller particles generally emit higher-energy light. Composition, coatings and defects also play a role.

02 / WHERE IT LEADS

An application, in context

They are used to convert light in display systems and are being investigated for sensors. Controlling synthesis makes it possible to tune the optical response.