Two dancers on stage must move in perfect sync, but if one hesitates, the whole routine is ruined. That's roughly how quantum computers with neutral atoms work: two atoms are entangled by putting them into a Rydberg state (as huge as a balloon compared to an ordinary atom), and then you wait for them to 'dance' their part.
The trouble is that this dance usually lasts hundreds of nanoseconds. During that time, the balloon atom can pop — the Rydberg state is unstable and decays quickly. The longer the dance, the more errors. The authors figured out how to speed it up to 10 nanoseconds — faster than a lightning flash. To do this, they added 'handrails' to the stage: optical tweezers (laser traps) and a two-dimensional optical lattice. These tools gently guide the atoms, keeping them from falling out of rhythm due to jitter.
Previously, researchers were afraid to use the full interaction strength between Rydberg atoms because it is extremely sensitive to tiny displacements. Now, by controlling motion, you can turn on this force at full strength, perform the operation, and turn it off, barely heating the atoms (by less than 0.01 quanta of motion). Even if the traps shift by 50 nanometers, hundreds of times thinner than a hair, the scheme still works.
This gives rise to a new class of quantum gates: fast, precise, and robust against disturbances. The dance becomes swift, and errors melt away like morning mist.
Rydberg atoms are so large that their size can reach thousandths of a millimeter — almost like a bacterium. If an ordinary atom were the size of a cherry, a Rydberg atom would be the size of a football stadium.