This paper is a wide‑ranging review of neutral‑atom quantum computing. In this approach, lasers hold individual neutral atoms in place and the atoms’ internal energy levels store quantum bits. The paper explains how researchers use highly excited “Rydberg” states — in which an electron orbits far from the nucleus — to make atoms interact strongly enough to perform quantum logic gates. It surveys the main technical routes, recent experimental milestones up through 2026, and the engineering challenges that remain.

The authors walk through the basic pieces of the platform. A common encoding uses hyperfine states of alkali atoms such as rubidium‑87 or cesium‑133 as the |0⟩ and |1⟩ states; these states can keep their quantum information for seconds, while gate operations happen on microsecond time scales. Some groups use alkaline‑earth atoms (for example strontium‑87 or ytterbium‑171) and exploit long‑lived “clock” states tied to the atom’s nuclear spin, which can give even longer coherence. Rydberg states are excited with two lasers in a two‑photon process; because Rydberg atoms are physically large and strongly polarizable, two atoms in Rydberg states can interact with strengths of tens of megahertz at distances of about 10 micrometers.

The review compares three mainstream hardware routes. Optical tweezer arrays use tightly focused laser beams (split and steered by acousto‑optic deflectors or spatial light modulators) to trap and move single atoms. Optical lattices form dense, regular arrays by interfering laser beams and are useful for very large, uniform arrays. Dipole‑trap arrays made with microlens optics sit between those two approaches. A typical experimental cycle described in the paper is: capture and cool atoms in a magneto‑optical trap (MOT), load them randomly into traps, image to see which sites are filled, rearrange atoms to remove holes, run quantum operations, and finally read out the results.