Designing out-of-equilibrium quantum systems

The aim of this project is to explore, understand, and ultimately design forms of out-of-equilibrium quantum dynamics that are relevant for future technologies, by using quantum simulators based on atomic gases in optical potentials. Ultracold gases are a unique platform in that they offer controllability and versatility in the quantum regime that is currently unparalleled by any other quantum system. IN the future, ultracold atom simulations will help planning and designing out-of-equilibrium many-body quantum dynamics similarly to how wind tunnels are utilized in aerodynamics.
The goal of this project will be to develop a so-called quantum-gas microscope setup with tuneable interaction and novel lattice geometries, including access to double wells and triangular lattices. This will make it possible to study out-of-equilibrium magnetic properties with access to local measurement and addressing, and allow for the realisation of frustrated magnetism in triangular lattices.
The design of the apparatus will build on the existing experience in the group in building quantum-gas microscopes using rubidium-87 atoms. The heart of the apparatus is a high-resolution optical microscope of numerical aperture NA=0.68 to provide a diffraction-limited resolution of ~600 nm at a wavelength of 780 nm, close to the spacing between the lattice sites. In contrast to previous quantum-gas microscope setups, we will use an all-optical approach that will enable a much faster repetition rate, and allow for the later inclusion of rubidium-85 atoms. This approach is based on the work by other groups who recently reported trapping and cooling large numbers of rubidium 85 in a hybrid trap configuration.
The 3.5 years of the research programme within this PhD studentship can be divided into the following steps. Step 1: Setup of the laser system for 780nm, setup of an ultrahigh vacuum chamber. Step 2: Creation of a two-dimensional and three-dimensional magneto-optical trap, evaporative cooling of rubiduim in magnetic and optical traps to reach a Bose-Einstein condensation. Step 3: Setup of the optical lattice and corresponding laser sources, consisting of three pairs of counter-propagating laser beams. Loading of the atoms into the optical lattice. Step 4: Setup and characterization of the high-resolution imaging system, observe single-atom resolved fluorescence detection. Step 5. Loading of a Bose-Einstein condensate into the optical lattice and realisation of the superfluid-to-Mott insulator transition.