  Trapped ions boast long coherence times and excellent gate fidelities, making
them a useful platform for quantum information processing. Scaling to larger
numbers of ion qubits in RF Paul traps demands great effort. Another technique
for trapping ions is via a Penning trap where a 2D crystal of hundreds of ions
is formed by controlling the rotation of the ions in the presence of a strong
magnetic field. However, the rotation of the ion crystal makes single ion
addressability a significant challenge. We propose a protocol that takes
advantage of a deformable mirror to introduce AC Stark shift patterns that are
static in the rotating frame of the crystal. Through numerical simulations we
validate the potential of this protocol to perform high-fidelity single-ion
gates in crystalline arrays of hundreds of ions.
