Single-, Few- and Many-Body Physics in Optical Superlattices

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

This project will use an ensemble of neutral atoms cooled to temperatures lower than anywhere else in the known Universe, held in a crystal formed by intersecting laser beams, superbly isolated from the outside world, and detected with highly sensitive imaging methods, to model and understand the properties of solid-state materials. The broad goal of this work is to promote the progress of science in two specific areas that are presently of high scientific and economic interest. First, experiments on these ultracold atomic gases will unravel central mysteries in materials science, specifically those pertaining to materials with strongly correlated electrons and frustrated magnetic interactions, both of which lead to novel phases of matter. These novel phases may enable advances in information storage, information processing, or high-temperature superconductivity. Second, this project advances capabilities in preparing and controlling complex quantum systems. These capabilities are expected to fuel the development of new quantum technologies. In fact, the graduate students and postdoctoral researchers conducting this work will gain valuable skills and be positioned to make significant contributions to the nascent quantum technologies sector, as well as in academic and other research positions. More specifically, this project focuses on the quantum properties of itinerant particles in two new non-primitive two-dimensional crystal structures: a trimerized Kagome lattice and a hexamerized honeycomb lattice. In the current experimental setup, the itinerant particles are rubidium atoms and the crystal structure is formed using a bichromatic optical lattice. In both lattice structures, strongly bonded multi-site plaquettes are coupled weakly to one another. In the limit of zero coupling between plaquettes, the lattices are composed of many fully isolated, few-site, few-particle quantum systems. Measurements will probe the single-body and few-body quantum states of these plaquettes, advancing our capabilities in quantum state engineering and realizing minimal representations of bosonic Laughlin states. In the regime where coupling between plaquettes is introduced, many-body physics emerges in a controlled manner. Measurements will be performed to reveal interesting orbital-magnetism states and characterize rapidly rotating lattice-trapped quantum gases. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.