Trapping Ion Coulomb Crystals in an Optical Lattice.

We report the optical trapping of multiple ions localized at individual lattice sites of a one-dimensional optical lattice. We observe a fivefold increased range of axial dc-electric field strength for which ions can be optically trapped with high probability and an increase of the axial eigenfrequency by 2 orders of magnitude compared to an optical dipole trap without interference but of similar intensity. Our findings motivate an alternative pathway to extend arrays of trapped ions in size and dimension, enabling quantum simulations with particles interacting at long range.

Observation of Feshbach resonances between a single ion and ultracold atoms.

The control of physical systems and their dynamics on the level of individual quanta underpins both fundamental science and quantum technologies. Trapped atomic and molecular systems, neutral and charged, are at the forefront of quantum science. Their extraordinary level of control is evidenced by numerous applications in quantum information processing and quantum metrology.

Mass-selective removal of ions from Paul traps using parametric excitation.

We study a method for mass-selective removal of ions from a Paul trap by parametric excitation. This can be achieved by applying an oscillating electric quadrupole field at twice the secular frequency using pairs of opposing electrodes. While excitation near the resonance with the secular frequency only leads to a linear increase of the amplitude with excitation duration, parametric excitation near results in an exponential increase of the amplitude.