Equilibration of the planar modes of ultracold two-dimensional ion crystals in a Penning trap

Planar thermal equilibration is studied using direct numerical simulations of ultracold two-dimensional ion crystals in a Penning trap with a rotating wall. The large magnetic field of the trap splits the modes that describe in-plane motion of the ions into two branches: high-frequency cyclotron modes dominated by kinetic energy and low-frequency \mathbf{E}\ifmmode\times\else\texttimes\fi{}\mathbf{B}modes dominated by potential energy...