Dissertation Defense: Grant Schumacher, Yale University, “Stability of a Three-Component Fermi Gas”

Event time: 
Friday, April 12, 2024 - 2:00pm to 3:00pm
Sloane Physics Laboratory SLP, Room 63 See map
217 Prospect Street
New Haven, CT 06511
Grant Schumacher, Yale University
Event description: 

Ultracold quantum gases have proven to be powerful platforms for quantum simulation, due to their precision and tunability. In particular, ultracold gas experiments have made many fundamental contributions to understanding the two-component (spin-1/2) Fermi gas. Utilizing higher spin systems would open far-reaching opportunities for quantum simulation, such as SU(N) Fermi gases, however such experiments have been much rarer.
Here I report our experiments characterizing the stability of the three-component Fermi gas. This system displays loss resonances related to Efimov physics, however previous experimental work was restricted to studying the spin-balanced (unpolarized) gas in harmonic traps. We expand on these measurements by studying the stability of a uniform system with controllable polarization. We find anomalous loss behavior that qualitatively disagrees with previous assumptions about the nature of these losses. We develop a generalized loss equation to model this behavior, and we systematically rule out various technical explanations. Finally, we present a conjectural model which may hint at the ultimate explanation of this surprising behavior.
Thesis Advisor: Nir Navon
Committee: Yoram Alhassid, Jack Harris, Charles Brown, and Chris Greene (Purdue University)