Quantum Simulation and Precision Spectroscopy in Compact Penning Ion Traps*

Cold, trapped atomic ions form the basis of many state-of-the-art quantum technologies including sensors, clocks, simulators, and computers. Penning traps allow confinement of charged particles within a combination of static electric and magnetic fields, permitting coherent manipulation of trapped-ion qubits with minimal environmental perturbations. In recent decades, researchers have demonstrated ion confinement in compact Penning ion traps based on permanent magnets, reducing the experimental overhead required for trapped-ion experiments at high magnetic field. We describe our recent demonstrations of Doppler cooling and spectroscopy of ⁴⁰Ca⁺ and ⁹Be⁺ in novel, permanent-magnet-based, compact Penning traps [1, 2]. We also discuss progress towards optical addressing of individual ⁴⁰Ca⁺ ions within a rotating two-dimensional Coulomb crystal and applications for quantum simulation (e.g. quantum approximate optimization algorithms).