Atomic Physics

James K. Thompson describes how photons repeatedly reflected inside an optical cavity can couple laser-cooled atoms. These collective interactions provide tools for both simulating many-body systems and improving precision measurements. The seminar examines ways to shape the coupling, including exchange and XYZ interactions, interactions involving three or four particles, dissipative processes and protection of coherence through a many-body energy gap. Applications include studying time-dependent phases of superconductors, increasing the sensitivity of matter-wave interferometers and advancing optical clocks. The organizer provides both an Ann Arbor venue and an online attendance option.

Lawrence Cheuk presents experiments using laser-cooled polar molecules held in optical-tweezer arrays. Molecular internal states and electric-dipole interactions provide resources for quantum computation, simulation and precision measurement. The talk covers preparation, control and detection of individual molecules; two-qubit operations and deterministic molecular entanglement; and one-dimensional spin simulations. Those experiments examine how spin excitations move, form bound pairs and undergo coherent pair creation and removal. A second set of experiments generates molecular spin-squeezed states and uses spatially resolved measurements to investigate reduced measurement noise, bipartite entanglement and Einstein-Podolsky-Rosen steering. Preliminary progress toward larger arrays may also be discussed. The Donald R. Hamilton Colloquium takes place in Jadwin Hall A-10 at Princeton University.