Quantum mechanics

Rydberg atom

Quantum computer

Engineering

Rydberg formula

Quantum gate

Toffoli gate

Atomic physics

Plasma

Parallel computing

Computer science

Energetic neutral atom

Physics

Ionization

Atom (system on chip)

Quantum

Qubit

Topology (electrical circuits)

Electrical engineering

Physical Review Letters

We report the implementation of universal two- and three-qubit entangling gates on neutral atom qubits encoded in long-lived hyperfine ground states. The gates are mediated by excitation to strongly interacting Rydberg states, and are implemented in parallel on several clusters of atoms in a one-dimensional array of optical tweezers. Specifically, we realize the controlled-phase gate, enacted by a novel, fast protocol involving only global coupling of two qubits to Rydberg states. We benchmark this operation by preparing Bell states with fidelity $\mathcal{F} \ge 95.0(2)\%$, and extract gate fidelity $\ge 97.4(3)\%,$ averaged across five atom pairs. In addition, we report a proof-of-principle implementation of the three-qubit Toffoli gate, in which two control atoms simultaneously constrain the behavior of one target atom. These experiments demonstrate key ingredients for high-fidelity quantum information processing in a scalable neutral atom platform.

Parallel Implementation of High-Fidelity Multiqubit Gates with Neutral Atoms