Correlation energy of a homogeneous dipolar Fermi gas

TL;DR

This paper investigates the correlation energy in a 3D homogeneous dipolar Fermi gas beyond Hartree-Fock, revealing stronger correlations and a lower collapse threshold, and proposes a new energy functional for trapped systems.

Contribution

It introduces a calculation of correlation energy beyond Hartree-Fock for dipolar Fermi gases and proposes a new energy functional for trapped configurations.

Findings

Correlation energy is comparable to Fock energy, indicating strong correlations.

The critical density for mechanical collapse is lower than previously estimated.

A new energy functional for trapped dipolar Fermi gases is developed.

Abstract

We study the normal state of a 3-$d$ homogeneous dipolar Fermi gas beyond the Hartree-Fock approximation. The correlation energy is found of the same order as the Fock energy, unusually strong for a Fermi-liquid system. As a result, the critical density of mechanical collapse is smaller than that estimated in the Hartree-Fock approximation. With the correlation energy included, a new energy functional is proposed for the trapped system, and its property is explored.