Dynamical Properties of the One-Dimensional Supersymmetric t-J Model: A View from Elementary Excitations

TL;DR

This paper investigates the dynamical properties of the one-dimensional supersymmetric t-J model with inverse-square interactions, revealing insights into excitation spectra and supermultiplet structures through numerical and analytical methods.

Contribution

It introduces a simple rule to understand supermultiplet structures and compares dynamical properties with related models, advancing understanding of supersymmetric t-J systems.

Findings

Dynamical spin structure factor is density-independent when only two spinons contribute.

Strong correspondence between three-spinon plus one-holon states and two-spinon excitations in the Haldane-Shastry model.

Numerical results align with analytical predictions for excitation spectra.

Abstract

Dynamical properties, such as dynamical spin and charge structure factors and single-particle spectral functions, are studied for the one-dimensional supersymmetric t-J model with inverse-square interaction. Exact diagonalization and the recursion method are used for finite systems up to 16 sites. A simple rule is proposed to understand the supermultiplet structure in the excitation spectrum. Numerical calculations show that the dynamical spin structure factor is independent of the electron density in the region where only two spinons contribute. In the electron removal spectrum from half-filling, close correspondence is found between the dominant contribution from three-spinon plus one-holon states in the t-J model and the two-spinon excitations in the Haldane-Shastry model. Comparison is made with dynamics of the nearest-neighbor supersymmetric t-J model.