Dynamics of large samples of repulsive Fermi gases at nonzero temperatures

TL;DR

This paper presents a model for large, nonzero temperature fermionic mixtures to analyze their dynamics, revealing phase transitions and oscillation behaviors consistent with experiments and theoretical calculations.

Contribution

It introduces a scalable model for large fermionic systems at finite temperatures, enabling detailed study of their dynamic responses and phase behavior.

Findings

Ferromagnetic phase emerges at higher repulsion and temperature.

Good agreement with experimental data on radial oscillations.

Comparison with Hartree-Fock calculations validates the model.

Abstract

We develop a model of a binary fermionic mixture, consisting of large number of atoms, applicable at nonzero temperatures, in the normal phase. We use this approach to study dynamics of degenerate Fermi systems under various perturbations. For example, we analyze spin-dipole oscillations of a two-component fermionic mixture, demonstrating that the ferromagnetic phase shows up at stronger repulsion between components while the temperature raises. We study as well the radial oscillations of weakly interacting repulsive Fermi gases. We obtain a good agreement with experimental data when available. Otherwise, we compare our results with the outcome of the Hartree-Fock orbital calculations done for the system with small number of fermions.