Spectroscopic evidence for engineered hadron formation in repulsive fermionic $\textrm{SU}(N)$ Hubbard Models

TL;DR

This paper demonstrates spectroscopic detection of dynamical hadron formation in ultracold atomic systems modeled by the repulsive SU(N) Hubbard model, revealing meson and baryon emergence and interactions during time evolution.

Contribution

It provides the first spectroscopic evidence of hadron formation in a condensed matter analog using ultracold atoms in the SU(N) Hubbard model, including baryon dynamics.

Findings

Baryons and mesons are generated during system evolution.

Baryons become heavy and attract each other in the strong interaction limit.

Residual interactions lead to meson diffusion and long-term hadron presence.

Abstract

Particle formation represents a central theme in various branches of physics, often associated to confinement. Here we show that dynamical hadron formation can be spectroscopically detected in an ultracold atomic setting within the most paradigmatic and simplest model of condensed matter physics, the repulsive $\textrm{SU}(N)$ Hubbard model. By starting from an appropriately engineered initial state of the ${{\textrm{SU}(3)}}$ Hubbard model, not only mesons (doublons) but also baryons (trions) are naturally generated during the time evolution. In the strongly interacting limit, baryons become heavy and attract each other strongly, and their residual interaction with mesons generates meson diffusion, as captured by the evolution of the equal time density correlation function. Hadrons remain present in the long time limit, while the system thermalizes to a negative temperature state. Our conclusions extend to a large variety of initial conditions, all spatial dimensions, and for SU($N>2$) Hubbard models.