Fractional Excitations in Cold Atomic Gases

TL;DR

This paper investigates fractional excitations in a tilted 1D Bose-Hubbard model, deriving an analytic model and confirming results with simulations, paving the way for experimental detection of fractional particles in cold gases.

Contribution

It introduces an analytic perturbative model for fractional excitations and demonstrates the existence of bound states, validated by t-DMRG simulations.

Findings

Existence of fractional domain-wall excitations.

Identification of a repulsively bound state above a critical momentum.

Validation of the model through numerical simulations.

Abstract

We study the behavior of excitations in the tilted one-dimensional Bose-Hubbard model. In the phase with broken symmetry, fundamental excitations are domain-walls which show fractional statistics. Using perturbation theory, we derive an analytic model for the time evolution of these fractional excitations, and demonstrate the existence of a repulsively bound state above a critical center of mass momentum. The validity of the perturbative analysis is confirmed by the use of t- DMRG simulations. These findings open the path for experimental detection of fractional particles in cold atomic gases.