Sprecher
Beschreibung
Recent experiments with ultracold fermionic gases have demonstrated that even in extremely small systems with only 10 atoms, fluid-like behaviour can emerge [1]. As this is far outside the traditional regime of applicability for hydrodynamics, this ongoing project seeks to understand how this can arise from the microscopic interactions. We briefly review density functional theory (DFT) and explain how it can be used to bridge few- to many-body physics for both stationary and dynamic computations. We then motivate a specific functional to describe strongly interacting Fermi systems, the superfluid local density approximation (SLDA) [2], which we have used to model the initial profile and subsequent dynamics of 10 strongly interacting fermionic atoms confined in two dimensions by an optical trap. We present some of our recent results showing remarkable agreement with the experimental data for the initial density profile of such a system. We further show that the time-dependent DFT computation qualitatively reproduces interaction-driven elliptic flow, providing a preliminary theoretical account of emergent collective behaviour in this few-body system.
References
[1] S. Brandstetter et al., “Emergent interaction-driven elliptic flow of few fermionic atoms,” Nat. Phys., vol. 21, no. 1, pp. 52–56, Jan. 2025, doi: 10.1038/s41567-024-02705-8.
[2] G. Wlazłowski, P. Magierski, M. M. Forbes, and A. Bulgac, “W-SLDA Toolkit: A simulation platform for ultracold Fermi gases,” Feb. 09, 2026, arXiv: arXiv:2602.08982. doi: 10.48550/arXiv.2602.08982