Spectrum of Low-Lying Excitations in a Supersymmetric Extended Hubbard Model

TL;DR

This paper investigates the excitation spectrum and thermodynamics of a one-dimensional supersymmetric extended Hubbard model, revealing diverse excitations and differences based on interaction type.

Contribution

It provides a detailed analysis of low-lying excitations and thermodynamics in a supersymmetric Hubbard model, including new insights into bound states and interaction effects.

Findings

Identification of various excitations including spinons, holons, and localons.

Spectral differences between repulsive and attractive interactions.

Thermodynamic properties of the model analyzed.

Abstract

We continue the study of the $u(2|2)$-supersymmetric extension of the Hubbard model in one dimension. We determine the excitation spectrum at zero temperature even in the sectors where the ground states are $u(2|2)$-descendants of Bethe states. The excitations include spinons, holons, electrons, localons (local electrons pairs, moving coherently through the lattice) and their bound states. The spectra are found to be very different for repulsive and attractive on-site interaction. We also study the thermodynamics of the model.