Deterministic preparation of single potassium atoms in microtrap arrays for the quantum simulation of spin systems.

• Applicant: Professor Dr. Christian Groß
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2016 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 316159385

The goal of the proposed project is the study of deterministically prepared Rydberg many-body systems in microtrap arrays. The realization of flexible synthetic quantum magnets will be in the focus of the project. We aim to realize systems with long-range interactions and sizes up to one hundred spins, in which single spins are experimentally observable. To this end, we will advance a recently demonstrated method for the preparation of single atoms in microtraps. We will utilize the special properties of potassium, that is, the ideal internal level-structure for deterministic loading of 1064nm microtraps. By that, we are confident to increase the loading fidelity well beyond the 90% recently demonstrated for Rubidium. Two-dimensional microtrap arrays come with the great advantage of flexible geometry tuning. In particular, they enable the realization of arrays with large distance between the individual traps, such that the strength of the Rydberg-Rydberg interaction between atoms in these traps is in the experimentally accessible range.Based on the microtrap array we will study long-range interacting transverse Ising magnets. Previous experiments on such systems were limited to the regime of very small magnetization or system size. This project will push this limit to enable experiments in regimes that are not accessible by calculations on classical computers. The single atom sensitive detection and the high data rate of the experiment will then allow for a precise characterization of the quantum magnets in- as well as out-of-equilibrium.Furthermore, we will study decoherence in off-resonantly laser coupled Rydberg gases. The advantage of the microtrap array is here the flexible geometry and variable atomic distances for intermediate system sizes. We aim at the in-depth understanding of coherence limiting processes, and their subsequent minimization, in Rydberg dressed systems.The project belongs into the many-body physics category of the GiRyd priority program. We will collaborate with several national groups for the detailed theoretical description of various aspects of the proposed experiments.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1929: Giant Interactions in Rydberg Systems (GiRyd)