RII Track-4:FAST: Numerical Simulations of Bose-Einstein Condensates in Microgravity (NumeriCAL)

Middlebury College, Middlebury VT

Investigators

Abstract

When cooled to extremely low temperatures, certain types of atoms can form a quantum mechanical phase of matter known as a Bose-Einstein Condensate (BEC). In a BEC, the wave-like nature of matter becomes macroscopically apparent, as a large number of atoms occupy the same quantum mechanical state. Experiments have demonstrated the macroscopic quantum mechanical behavior of BECs, including the interference of matter-waves, quantum superpositions of matter on macroscopic length scales, and quantum mechanical vortices. BECs have the potential to be a platform for quantum technologies such as ultra-sensitive quantum detectors and quantum computers. NASA's Cold Atom Laboratory (CAL) is a unique experimental system that allows for BEC experiments to be performed on the International Space Station. Recently, CAL has been used to create and manipulate BECs in the microgravity environment of Earth's orbit. This project aims to further the characterization, understanding, and development of these fundamental experiments by developing numerical simulations of the BECs formed in CAL experiments. This work will be done in collaboration with undergraduate student trainees and the CAL experimental team at NASA’s Jet Propulsion Laboratory. These simulations will facilitate future CAL experiments in probing fundamental physics in ways that are not achievable in terrestrial experiments. This project will develop numerical simulations of ultracold atom experiments performed in NASA's Cold Atom Laboratory (CAL) on the International Space Station. The unique experimental capability of the CAL instrument enables probing quantum many-body systems in new regimes of temperatures and densities and allows for matter wave interferometry with higher sensitivity than can be achieved in terrestrial experiments. Recently, CAL has been used to create and manipulate Bose-Einstein Condensates (BEC) in the microgravity environment of earth’s orbit. Future experiments involving CAL and related technologies could include high precision tests of fundamental physics such as searches for dark energy, tests of Einstein's equivalence principle, and gravitational wave detectors. However, the compact design and atom-chip based technology used in CAL can lead to undesired field gradients and local perturbations to the trapping potential, which can limit the range of accessible temperatures and lead to asymmetries and fragmentation of the BEC. The PI will develop path integral Monte Carlo simulations of trapped ultracold bosons that model CAL experiments. These simulations will help characterize the CAL experimental system, interpret experimental data, and develop future experiments. Numerical studies will address fragmentation of the BEC, limitations to the accessible temperatures & densities, immiscibility in binary BEC mixtures, and loss of symmetry in bubble-BEC experiments. These numerical simulations will aid the CAL experimental team in pushing the limit of their experiments and advance investigations of fundamental physics. 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.