Trapped-Ion Qubits

Qubits stored in the electronic states of individual ions held by electromagnetic fields — long coherence and high-fidelity gates.

In brief

• Ions confined in Paul traps; states manipulated with lasers.
• Excellent coherence and gate fidelity; all-to-all connectivity.
• Slower gates and harder scaling than solid-state qubits.
• Cryogenic operation improves vacuum and stability.

The detail

Trapped ions offer some of the highest gate fidelities demonstrated. Their coherence is outstanding, though scaling to many ions and speeding up gates are active challenges. Cryogenic ion traps improve vacuum quality and coherence, adding to the industry's cold-infrastructure demand.