Quantum Statistics of a Shell-Shaped Bose-Einstein Condensate

Brendan Rhyno, Courtney Lannert, Nathan E. Lundblad +2 more

Lydia Shannon, Courtney Lannert

Brendan Rhyno, Karmela Padavić, Kuei Sun +3 more

Patrick Boegel, Alexander Wolf, Matthias Meister +1 more

Abstract Motivated by the recent experimental realization of ultracold quantum gases in shell topology, we propose a straightforward implementation of matter-wave lensing techniques for shell-shaped Bose–Einstein condensates. This approach allows to significantly extend the free evolution time of the condensate shell after release from the trap and enables the study of novel quantum many-body effects on curved geometries. With both analytical and numerical methods we derive optimal parameters for realistic schemes to conserve the shell shape of the condensate for times up to hundreds of milliseconds.

Hu Huang, Shiqun Li

Zerong Huang, K. Lee, Chun Kit Wong +4 more

We investigate the hollowing transition of a shell-shaped Bose-Einstein condensate using collective excitations. The shell is created using an immiscible dual-species Bose-Einstein condensate mixture, with its hollowness controlled by tuning the repulsive interspecies interaction via a Feshbach resonance. Our results reveal two distinct monopole modes in which the two condensates oscillate either in phase or out of phase. The spectrum of the out-of-phase mode exhibits a nonmonotonic dependence on the interspecies interaction, providing a clear signature of the topology change from a filled to a hollow condensate. Furthermore, we find that the critical point of the hollowing transition depends strongly on the number ratio of the two species. Our findings provide a detailed understanding of the topology change in shell-shaped quantum gases and pave the way for future study of quantum many-body phenomena in curved spaces.