Search for Universality in the Dynamics of Strongly Correlated Ultracold Fermions

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The world around us is constantly changing. Out of these dynamics, equilibrium order can emerge. But the everyday dynamics we identify as life itself cannot exist in equilibrium, because (for instance) gradients in ion concentrations drive action potentials in nerves. Non-equilibrium dynamics are studied diversely, in cosmology of the early Universe, in economic market dynamics, in quark-gluon plasma in heavy-ion collisions, and in the resistivity of superconductors. I propose experiments with ultracold atoms that study dynamics. When cooled to the nanokelvin regime, the fermionic isotope of neutral potassium can emulate the behaviour of electrons in solids, or even explore scenarios inaccessible with solid materials. In either case, the advantage of our "quantum simulation" approach using cold atoms is an unprecedented ability to tune and characterize the sample. This leaves no room for uncertainty about the model we explore, so that any phenomena or behaviour observed is a clear test of our understanding of many-body physics. The proposed research program will address three specific research objectives. A first series of experiments tunes principal-wave interactions in a quantum wire and measures particle-particle correlations. Can we find evidence of predicted duality between one-dimensional Bose and Fermi systems? A second series of experiments measures the conductivity of strongly interacting fermions in a perfect crystal. Is there a universal limit of resistivity? A third series of experiments will attempt to use the orbital degree of freedom to engineer new quantum states. The long-term goal of this research is to elucidate how inter-particle interactions limit relaxation processes, give rise to magnetism, and enable new quantum states. The proposed experiments are challenging, and yet the potential benefit is tremendous. The results of our investigations will yield direct insight into the unsolvable dynamics of paradigmatic models. The proposed work will provide a rewarding research experience for young scientists and engineers. Undergraduates, graduate students, and postdoctoral fellows will gain experience with lasers, digital and analog electronics, computer programming and control integration, vacuum technologies, microwave design, building mathematical models, and mechanical workshop skills. Professional development of these highly qualified personnel also includes leadership roles within the research group, travel to and presentations at international conferences, and involvement with public education, tours, and lectures.