Charge and Spin Transport in the One-dimensional Hubbard Model

TL;DR

This paper investigates charge and spin transport in the 1D Hubbard model, revealing how different excitations carry spin or charge, using analytic and numerical Bethe-ansatz methods.

Contribution

It provides a detailed analysis of current spectra for elementary excitations in the 1D Hubbard model at half-filling, combining analytic and numerical approaches.

Findings

Spin-triplet excitations carry spin but no charge.

Charge η-spin triplet excitations carry charge but no spin.

Certain excitations carry neither spin nor charge currents.

Abstract

In this paper we study the charge and spin currents transported by the elementary excitations of the one-dimensional Hubbard model. The corresponding current spectra are obtained by both analytic methods and numerical solution of the Bethe-ansatz equations. For the case of half-filling, we find that the spin-triplet excitations carry spin but no charge, while charge $\eta$-spin triplet excitations carry charge but no spin, and both spin-singlet and charge $\eta$-spin-singlet excitations carry neither spin nor charge currents.