Lasse Vines

A silicon wafer is like cookie dough. Heat it in an oven, and tiny raisins appear inside — defects in the crystal lattice that can emit single photons. These "raisins" are called color centers, and they are needed for quantum computers and secure communication.

Hidden inside a zinc oxide crystal is a quantum duo: a tin atom and a lithium atom sitting side by side. Their bond is so tight that the electron captured by this pair seems to live on the tin, while the lithium merely plays along. This complex was long sought after, but only now has it been deliberately created and identified by its characteristic glow.