A Program in Ultralow-Temperature Atomic Physics

Massachusetts Institute Of Technology, Cambridge MA

Investigators

Abstract

The goal of this program is to study the properties of molecules and materials at a fundamental level. The result is new insights into the principles of chemistry and materials properties. The experimental program employs methods developed in atomic physics to control the motion of atoms with unprecedented precision. These well controlled building blocks can now be assembled into molecules or new materials like Lego pieces. This method 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 of these systems. This research program has two major directions: (1) Properties of magnetic materials (2) Quantum control of chemistry, studied in collisions of sodium lithium molecules, either with themselves, or with sodium atoms. This research 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. Results of this research will be used for public outreach through popular talks and publications. Magnetism or spin physics will be pursued on three different platforms which are complementary, but synergetic: rubidium, lithium, dysprosium. These three atoms have different properties, which allow the realization of different spin Hamiltonians. Lithium is the lightest atom and operates on a faster time scale. Dysprosium features dipolar interactions, and, together with rubidium, has a strong vector AC Stark shift which will be exploited for spin-dependent potentials. This approach should lead to major progress in realizing and characterizing new magnetic phases and understanding their dynamics. A major goal is the development of techniques to realize quantum phases with non-trivial topological properties such as the Haldane phase. The work on ultracold sodium lithium molecules realizes quantum control of chemistry by identifying and analyzing resonances in reactive and inelastic collisions. It will provide novel insight into collision complexes which form during molecular reactions. The work on sodium lithium molecules is also a step towards matter composed of more complicated building blocks: molecules instead of atoms. This research addresses important questions at the frontier of many-body physics and cold chemistry. Its ambitious goal is to advance cold atoms and molecules as a design tool for new materials in the form of quantum simulators. 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.