Tunneling through a potential barrier is one of the most basic and extraordinary features of quantum mechanics. It plays a key role in important technologies such as tunneling diodes and superconducting quantum interference devices (SQUIDs), both used in common devices ranging from electronics to biological measurements. Atomic, molecular, and optical theory has a long history of exploring fundamental questions in physics in tabletop experiments, from limits on the standard model of particle physics in studies of basic symmetries of the universe to time variation of fundamental physical constants in cold molecules. We will push the limits of quantum mechanics and disparate notions of what is macroscopic, in practical realizations in ultracold quantum gases. We focus on macroscopic quantum tunneling (MQT), i.e., tunneling of many particles at once, where very many outstanding problems remain unanswered. Bose-Einstein condensates and ultracold quantum gases provide an ideal context in which to explore MQT because they are highly tunable and controllable macroscopic quantum systems in which theoretical ideas can be realized directly in present experiments.
We have a multi-faceted approach to meet broader impact goals. First, we will continue to organize national and international workshops and conferences including the recent cold molecules program in Spring 2013. Second, we will work with large numbers of undergraduate researchers via the Colorado School of Mines' (CSM) senior design / senior thesis program, CSM's combined BS/MS programs, and the NSF Research Experience for Undergraduates program. Third, we will continue to foster an accepting, diverse environment within our research group to support underrepresented groups in physics. Finally, the training of students in rigorous numerical techniques and high-performance parallel computing is key to success in a number of arenas in society, from the space program to global climate change. We will train such students, and support a PI involved in that effort from the undergraduate through post-doctoral levels.
