Quantum many body physics with arrays of trapped ions
Trapped ions, when cooled to sufficiently low temperatures, form one, two, or three-dimensional crystalline arrays. The ions in these crystals are strongly coupled; the Coulomb potential energy far exceeds the ion thermal energy. Two atomic levels (a two-level system or effective spin) can be isolated and controlled in each atomic ion. By employing forces which depend on the internal atomic state (or spin) of an atomic ion, the Coulomb potential energy of the array can be modified in a spin-dependent way to mimic effective quantum spin Hamiltonians, enabling the experimental study of intractable problems in quantum magnetism. (See, for example, Kim, K. et al., “Quantum simulation of frustrated Ising spins with trapped ions,” Nature 465, 590–3 (2010) .) I will describe our work on implementing antiferromagnetic interactions on two-dimensional triangular arrays of hundreds of ions in a Penning trap.