A Program in Ultralow-Temperature Atomic Physics

The goal of this program is to study materials at a fundamental level. The result is a deeper understanding of important materials, and new insights into the principles of material properties. By creating and studying models of new materials, the researchers want to find out if speculative new materials can be realized in Nature. The experimental program employs methods developed in atomic physics to control the motion and orientation of atoms with unprecedented precision. Those well controlled building blocks can now be assembled into new materials like Lego pieces. These new materials may show behavior similar to naturally occurring materials which are not fully understood, or even display phenomena never seen before. Assembling new forms of matter with well separated atoms has the advantage that the building blocks and their interactions are well known, and therefore also the basic equations describing their behavior. This together leads to a platform where both theoretical methods (analyzing these equations) and experimental methods (using the precision of atomic physics) can be combined to obtain a deeper understanding for important materials and find new possibilities for synthesizing new materials. The major focus of the research program is on the question how strong magnetic fields and magnetic couplings (called spin-orbit coupling) change the properties of electrons in semiconductors and metals. Since our Lego pieces are neutral atoms, real magnetic fields are replaced by so-called synthetic magnetic fields created with the help of laser beams. In addition, the researchers will study fundamental aspects of ferromagnetism, and create ultracold molecules. The realization of new forms of ultracold matter will advance our understanding of materials and provide guiding principles for materials research. The proposed work is fundamental in its immediate impact, but in the long run, it should lead to devices and advanced materials with yet unknown properties, and open new possibilities and applications. Besides promoting the progress of science; this program educates students and postdocs and prepares them for a career in areas of advanced technology.

More technically, the goal of this project is to further advance the use of cold atoms as model systems for strongly correlated matter, but also to take this approach to the next level by creating materials with no known counterpart in Nature. In the spirit of quantum simulations, samples will be prepared which are the simplest possible realizations of many-body Hamiltonians representing idealized paradigmatic forms of matter. The major foci of the proposed research in the next five years are the themes of synthetic gauge fields and spin orbit coupling. These goals make strong connections with current frontiers in many-body theory and in condensed matter physics, including the quantum Hall effect, topological insulators, and strongly correlated states. These materials are more profoundly quantum mechanical than ordinary materials because they exploit non-trivial quantum mechanical phases (geometric phases, Berry phase) or quantum entanglement. In addition,it is planned to explore itinerant ferromagnetism, cooling to picokelvin temperatures using adiabatic state preparation, and the sodium-lithium dimer as a heteronuclear dipolar molecule.