Optical Hyperfine Qudit Gates in Trapped Neutral Atoms

Neutral atoms have rapidly advanced as a leading platform for quantum information processing. Among them, alkaline-earth and alkaline-earth-like atoms stand out for their exceptionally long-lived qubit states, well-characterized hyperfine structures, and precise controllability via external fields. Their rich internal level structures also enable the realization of qudits – multi-level quantum systems that can increase information density and reduce circuit depth compared to conventional qubits.

In this work, we introduce a fast and robust method for performing single-qudit gate operations in alkaline-earth(-like) atoms subjected to moderate to strong magnetic fields. Our scheme is based entirely on optical interactions and avoids the use of oscillating magnetic fields. By tailoring the optical control parameters, we demonstrate that transitions between neighboring hyperfine levels can be coherently driven at rates of several kilohertz with high fidelity using single-beam Raman transitions.

A detailed theoretical analysis of the 1S0 to 3P1 optical transition reveals the magnetic-field and laser parameters required for universal single-qudit control. Numerical simulations further show that our approach achieves faster spin manipulation than existing state-of-the-art methods. These results establish a promising route toward efficient nuclear spin control in atomic systems, opening new avenues for quantum memories and other quantum technologies.