M. Saffman

A grain-of-sand-sized device: a tiny mirror-dish holds a single rubidium atom and collects the glow it emits under a laser beam. The trapped light particles are sent into an optical fiber — the whole setup is precise and stays aligned even when shaken.

A quantum computer is like an orchestra where each musician plays their own part, but all must sound in harmony. Until now, most quantum circuits were built from identical atoms — as if the orchestra consisted only of violins. Now physicists have taught two different elements to work together: rubidium and cesium.