Dynamical hadron formation in long-range interacting quantum spin chains

TL;DR

This paper investigates how mesons and more complex hadronic boundstates form dynamically in long-range interacting quantum spin chains, proposing protocols for their experimental observation in quantum simulators.

Contribution

It introduces the concept of dynamical hadron formation in quantum spin chains with long-range interactions and proposes protocols for observing these phenomena experimentally.

Findings

Meson scattering dominates elastic interactions.

Novel multi-particle boundstates like tetraquarks can form dynamically.

Protocols enable clear observation of hadron formation.

Abstract

The study of confinement in quantum spin chains has seen a large surge of interest in recent years. It is not only important for understanding a range of effective one-dimensional condensed matter realizations, but also shares some of the non-perturbative physics with quantum chromodynamics (QCD) which makes it a prime target for current quantum simulation efforts. In analogy with QCD, the confinement-induced two-particle boundstates that appear in these models are dubbed mesons. Here, we study scattering events due to meson collisions in a quantum spin chain with long-range interactions such that two mesons have an extended interaction. We show how novel hadronic boundstates, e.g. with four constituent particles akin to tetraquarks, may form dynamically in fusion events. In a natural collision their signal is weak as elastic meson scattering dominates. However, we propose two controllable protocols which allow for a clear observation of dynamical hadron formation. We discuss how this physics can be simulated in trapped ion or Rydberg atom set-ups.