Atom arrays with resonant dipolar exchange interactions
This project will study out-of-equilibrium dynamics of isolated and dissipative quantum systems, and interacting topological matter using a new type of synthetic many-body system pioneered in my group: assembled arrays of individual laser-cooled atoms held in microscopic optical traps. Unlike most traditional approaches exploiting van der Waals interactions, here the atoms will be coupled by resonant dipole interactions, a new opportunity that we introduced recently. This interaction naturally realizes a spin model where the spin excitations behave as particles hopping between sites and strongly interact with each other. The unique feature of this interaction is that it allows for the exploration of many-body problems both in a unitary regime where the interactions are fully conservative, and in a regime with collective dissipation by the emission of light. We will investigate these two situations using two different setups. The unitary regime will rely on an existing platform where rubidium atoms are excited to Rydberg states to implement large interactions. The dissipative regime will be explored on a new apparatus specifically built for the study of controlled, collective dissipation. It will be based on arrays of individual dysprosium atoms coupled by resonant interactions on an optical transition. These interactions, combined with our ability to vary the geometry of the arrays, to perform high-fidelity manipulations of individual atoms and measure correlation functions, will allow us to address open questions, in collaboration with theorists. We will (i) investigate out-of-equilibrium quantum magnetism in spin systems, in particular with frustrated geometries; (ii) seek to obtain the first realization of a bosonic fractional topological insulator; (iii) prepare collective states with tailored coupling to light, study the emergence of quantum correlations in a dissipative regime, and generate a new kind of interaction-induced single-photon non-linearity. r