Antiferromagnetic spin correlation of SU($\mathcal{N}$) Fermi gas in an optical super-lattice

TL;DR

This study demonstrates enhanced antiferromagnetic spin correlations in an SU(4) Fermi gas within an optical lattice, highlighting the role of Pomeranchuk cooling and advancing the understanding of high-symmetry quantum magnetism.

Contribution

It provides the first direct observation of antiferromagnetic correlations in an SU(4) Fermi gas, showing increased correlations compared to SU(2) due to cooling effects.

Findings

Antiferromagnetic correlations are observed in SU(4) systems.

Correlation strength is enhanced in SU(4) compared to SU(2).

Pomeranchuk cooling contributes to the increased correlations.

Abstract

Large-spin cold atomic systems can exhibit unique phenomena that do not appear in spin-1/2 systems. We report the observation of nearest-neighbor antiferromagnetic spin correlations of a Fermi gas with SU($\mathcal{N}$) symmetry trapped in an optical lattice. The precise control of the spin degrees of freedom provided by an optical pumping technique enables us a straightforward comparison between the cases of SU(2) and SU(4). Our important finding is that the antiferromagnetic correlation is enhanced for the SU(4)-spin system compared with SU(2) as a consequence of a Pomeranchuk cooling effect. This work is an important step towards the realization of novel SU($\mathcal{N}>2$) quantum magnetism.