Improved quantum control of two-dimensional ion crystals in a Penning trap

Two-dimensional crystals of trapped ions in a Penning trap have enabled advances in quantum simulation and precision measurement. Because the crystal rotates at ~180 kHz, previous experiments were limited to global interactions, and poor cooling of in-plane motion reduced experimental fidelity. In this defense, I describe using a deformable mirror (DM) to apply patterned spin rotations in the rotating frame of the crystal. The DM also enables precise measurement of in-plane motion, allowing characterization of a novel cooling technique that reduces the in-plane temperature by roughly an order of magnitude, improving the stability and control of large, rotating ion crystals.