Fig. 1. Universal quantum operations for tweezer clocks.

a, We demonstrate a universal quantum processor based on optical clock qubits. This processor is designed to perform any computational task and is also a highly sensitive clock. To realize this device, we demonstrate high-fidelity entangling gates between optical clock qubits and circuits with dynamical reconfiguration. We combine these with local single-qubit rotations through subwavelength atomic shifts and local MCR. b, We use tweezer-trapped ⁸⁸Sr atoms. Qubits are based on the ultranarrow optical clock transition ¹S₀ ↔ ³P₀, and entangling operations are realized through transient excitation to a Rydberg state n³S₁. We use coherent superpositions of quantized motional states in tweezers to shelve protected clock qubits for mid-circuit detection of ancilla qubits. c, We identify two instances where these universal quantum operations can be used in optimizing quantum metrology: entangled state preparation for near-optimal probes and entanglement-assisted read-out with ancilla qubits, thus realizing quantum logic spectroscopy for neutral atoms.