Evidence for Bosonization in a three-dimensional gas of SU($N$) fermions

TL;DR

This study provides experimental evidence of bosonization in a three-dimensional SU(N) fermionic gas, showing that increasing internal states diminishes fermionic behavior, aligning with theoretical predictions and enabling control over quantum statistics.

Contribution

First direct demonstration of bosonization in 3D SU(N) fermions, confirming the N-scaling of contact and advancing quantum simulation of statistical transmutation.

Findings

Contact per spin approaches a constant with 1/N scaling

Bosonization verified through a measurable physical quantity

Experimental control over fermionic and bosonic statistics in 3D

Abstract

Blurring the boundary between bosons and fermions lies at the heart of a wide range of intriguing quantum phenomena in multiple disciplines, ranging from condensed matter physics and atomic, molecular and optical physics to high energy physics. One such example is a multi-component Fermi gas with SU($N$) symmetry that is expected to behave like spinless bosons in the large $N$ limit, where the large number of internal states weakens constraints from the Pauli exclusion principle. However, bosonization in SU($N$) fermions has never been established in high dimensions where exact solutions are absent. Here, we report direct evidence for bosonization in a SU($N$) fermionic ytterbium gas with tunable $N$ in three dimensions (3D). We measure contacts, the central quantity controlling dilute quantum gases, from the momentum distribution, and find that the contact per spin approaches a constant with a 1/$N$ scaling in the low fugacity regime consistent with our theoretical prediction. This scaling signifies the vanishing role of the fermionic statistics in thermodynamics, and allows us to verify bosonization through measuring a single physical quantity. Our work delivers a highly controllable quantum simulator to exchange the bosonic and fermionic statistics through tuning the internal degrees of freedom in any generic dimensions. It also suggests a new route towards exploring multi-component quantum systems and their underlying symmetries with contacts.