Bilayer crystals of trapped ions for quantum information processing: Equilibrium structure and normal modes

Trapped ion systems are a leading platform for quantum information processing, but they are currently limited to 1D and 2D arrays, which imposes restrictions on both their scalability and their range of applications. In this talk, we propose a path to overcome this limitation by demonstrating that Penning traps can be used to realize remarkably clean bilayer crystals, wherein hundreds of ions self-organize into two well-defined layers. We show how these bilayer crystals are made possible by the inclusion of an anharmonic trapping potential, which is readily implementable with current technology. We also study the normal modes of this system and discover salient differences compared to the modes of single-plane crystals. Our analysis of equilibrium bilayer crystals and their normal modes provides crucial insights into identifying new opportunities for quantum simulation and quantum sensing experiments on this new platform, that are not straightforward with 1D and 2D crystals.