The development of ultracold atomic gases with tunable interactions and dimensionality has led to a new era of precision studies of fundamental quantum mechanical phenomena. In the context of few-body bound states, experiments have until now focussed on bosons, which display the celebrated Efimov effect, where three identical bosons can form a fractal set of states related by a discrete scaling symmetry. However, such states are inherently unstable, and at present a new generation of experiments are emerging which use two different fermionic species. The interest here is that, unlike bosons, identical fermions naturally feel a centrifugal barrier, which prevents losses and can lead to stable bound states.
When the heteronuclear Fermi gas is confined to one spatial dimension it has been predicted that trimers (bound states of 1 light atom, 2 heavy atoms) can form, while more exotic bound states (p light, q heavy) can exist for a rational density ratio p/q and sufficient mass imbalance [1]. The question which this project will address is whether the same phenomenon can occur in the two-dimensional Fermi gas. Here much less is known, but trimers and tetramers are predicted to exist [2]. The question may be investigated using a combination of scattering theory and Feynman diagrams.
References
[1] E. Burovski, G. Orso, T. Jolicoeur, Phys. Rev. Lett. 103, 215301 (2009). [2] J. Levinsen and M. M. Parish, Phys. Rev. Lett. 110, 055304 (2013).Supervisor: Dr Jesper Levinsen
See https://www.monash.edu/science/schools/physics/honours/honours-project to apply.