Holons on a meandering stripe

TL;DR

This paper investigates how transverse fluctuations of a stripe in a 2D antiferromagnet affect charge dynamics, identifying holons as key excitations and proposing a model linking stripe motion to holon movement.

Contribution

It introduces a model where holons are the elementary excitations on a domain wall, linking stripe fluctuations to holon dynamics in a Hubbard model context.

Findings

Holons are mobile charge carriers residing on domain wall kinks.

Stripe fluctuations do not suppress charge-density order in the absence of spin excitations.

Transverse stripe dynamics can be modeled through holon motion.

Abstract

To study a possible effect of transverse fluctuations of a stripe in a 2D antiferromagnet on its charge dynamics, we identify elementary excitations of a weakly doped domain wall in the Hubbard model. Hartree-Fock numerics and analysis of fermion zero modes suggest that for U>=3t charged excitations are mobile holons, Q=1, S=0. Each holon resides on a kink in the position of the domain wall. We construct a simple model in which transverse stripe dynamics is induced solely by motion of the holons. In the absence of spin excitations (spinons, Q=0, S=1/2), stripe fluctuations DO NOT suppress a tendency to form a global charge-density order.