ISBN 9783843951562

978-3-8439-5156-2, Reihe Physik

Sebastian Weber
Accurate Quantum Simulations with Rydberg Atoms

192 Seiten, Dissertation Universität Stuttgart (2021), Softcover, A5

Zusammenfassung / Abstract

This thesis studies quantum simulations with Rydberg atoms. The idea of quantum simulations is to use a well-controllable quantum system to simulate another quantum system. Quantum simulations aim at prospectively solving challenging simulation problems classical computers cannot handle efficiently, such as exploring highly entangled many-body ground states and dynamics. We focus on so-called analog quantum simulations that implement the system to be simulated directly and avoid the overhead of universal gate-based approaches. The class of implementable systems depends on the characteristics of the underlying platform. In general, platforms for quantum simulations must be reliable and well-controllable. Moreover, interactions must be fast in comparison to the decoherence time. Platforms that fulfill these requirements are, for example, superconducting qubits and trapped ions. Another approach is to use neutral atoms in optical tweezers. The atoms can be made interact by exciting them to the Rydberg state, i.e., an electronic state with a high principal quantum number, and harnessing the strong dipolar interactions between Rydberg atoms. Rapid developments over the last decade made it possible to use this approach to simulate various spin Hamiltonians on arbitrary two- and three-dimensional lattices, even in regimes beyond an exact numerical treatment. The research covered in this thesis contributed to this progress by providing theory support for the experimental realization of quantum simulations. The first part of the thesis addresses the calculation of Rydberg interaction potentials and their dependence on experimental parameters. In the second part, we use our insights about Rydberg interactions and show how accurate quantum simulations with Rydberg atoms can be applied to study various quantum spin models. Specifically, we demonstrate how different topological phases can be investigated.