Cheng Chen

Fourteen rubidium atoms lined up like beads on a string. Each atom is a tiny magnet that can point up or down. Together they follow strict rules, similar to a train schedule: everything is predictable, everything repeats. But introduce a barely noticeable change, and the schedule goes off the rails.

Physicists took 114 rubidium atoms, cooled them to near absolute zero (as in experiments with liquid helium), and neatly arranged them in a honeycomb pattern. They then smoothly adjusted the interaction strength, as if slowly turning up the heat under a pot.

Quantum computing suffers from 'false notes' — errors that arise from the slightest inaccuracy. Now they are eliminated with the precision of tuning a concert grand piano. The idea traces back to the dreams of pioneers — David Deutsch and Peter Shor — of flawless operations.