Collective oscillations of a two-component Fermi gas on the repulsive branch

TL;DR

This paper investigates the collective oscillation frequencies of a two-component Fermi gas on the repulsive branch, exploring paramagnetic and ferromagnetic phases, using multiple theoretical approaches to understand excitation contributions.

Contribution

It provides a comparative analysis of collective modes in different magnetic phases of Fermi gases using both Hartree-Fock and density-functional methods.

Findings

Identification of oscillation frequencies in paramagnetic and ferromagnetic phases

Comparison of theoretical approaches for collective excitations

Insights into excitation contributions from various gas modes

Abstract

We calculate frequencies of collective oscillations of two-component Fermi gas that is kept on the repulsive branch of its energy spectrum. Not only is a paramagnetic phase explored, but also a ferromagnetically separated one. Both in-, and out-of-phase perturbations are investigated, showing contributions from various gas excitations. Additionally, we compare results coming from both time-dependent Hartree-Fock and density-functional approaches.