Abstract

Direct experimental access to some of the most intriguing and puzzling quantum phenomena is difficult due to their fragility to noise. Their simulation on conventional computers is impossible, since quantum behaviour is not efficiently translatable in classical language. However, one could gain deeper insight into complex quantum dynamics via experimentally simulating the quantum behaviour of interest in another quantum system, where not all but the relevant parameters and interactions can be controlled and robust effects detected sufficiently well. One example is simulating quantum-spin systems with trapped ions.

After a proof of principle experiment based on two ions/spins only, we aim to explore the limitations and prospects and the options for scaling to larger and two dimensional systems. On the one hand, we shortly present our new trapping architectures based on arrays of radio-frequency traps. On the other hand, we aim to trigger the discussion how to merge the advantages for quantum simulations with ions and optical lattices. As a first experimental step, we were able to trap an ion optically. We initialize the ion via trapping and laser cooling in our linear Paul trap, turn on the optical dipole trap and switch off the Paul trap. The time dependence of the optical trapping probability is investigated and the ion’s survival detected via resonance fluorescence in the reactivated Paul trap.

In the near future, we plan to realize cooling to increase the life time and to investigate the limitations on the coherence times. Loading two ions and/or one ion and atoms into the identical one-dimensional optical lattice could be explored. This approach demonstrates not only the feasibility of optically trapping ions, but allows to dream of scalable quantum simulations providing long range interaction and individual addressability. In addition, a new class of quantum simulations might become accessible, based on the potentially intriguing interplay between neutral and charged particles in common optical lattices. Furthermore, confining an ion and atoms in one common optical dipole trap might allow to investigate the most interesting physics of ultra cold collisions without the limitations set by radio-frequency driven micro-motion.