Towards interactions between single atoms in tweezers and trapped ion crystals

Neutral atoms and trapped ions are leading platforms for quantum computing, quantum simulation, and optical clocks. Hybrid atom-ion systems have seen substantial progress, with experiments typically involving ions immersed in ultracold atomic clouds [1-4]. A defining feature of these systems is the long-range polarization interaction, which leads to collision dynamics that remain classical at millikelvin energies, while lower temperatures reveal a rich and nonclassical quantum scattering [5].

Current implementations of hybrid atom-ion systems face several challenges which we address by introducing a novel platform. Our system is based on single Sr atoms trapped in optical tweezer potentials integrated into a Sr+ trapped-ion crystal. Here we will explore long-range interactions that occur when the atom is excited to a Rydberg state. Precise positioning of the optical tweezers enables deterministic control over the atom-ion separation, allowing interactions to be explored in the long-range regime where micromotion-induced energy exchange and close-range Langevin collisions are suppressed.

Together, these features will enable controlled interactions at the single-particle level and provide a pathway toward a coherent quantum interface between neutral-atom and trapped-ion registers.

[1] https://doi.org/10.1103/PhysRevA.95.032709

[2] https://doi.org/10.1103/PhysRevLett.117.243401

[3] https://doi.org/10.1103/PhysRevLett.102.223201

[4] https://doi.org/10.1103/PhysRevA.96.030703

[5] https://doi.org/10.1038/s41467-025-67915-x