Researchers have created a new type of "quantum operation" that is dramatically more stable than previous methods. The achievement brings one hardware design, in particular — neutral‑atom qubits — a step closer to powering useful quantum computers. Quantum computers use qubits that can exist in a state of 0, 1 or a superposition of both. Key to their processing power are "gates" capable of shuffling qubits between those states so they can run calculations in parallel. One critical type of gate is called a swap gate, which allows information to be routed through a machine by exchanging two qubits' states. Many quantum systems rely on highly excited electronic states or collisions between atoms, as well as on the tunnel effect , in which particles slip through obstacles that would be impassable according to classical physics.…