Boundary effects on one-particle spectra of Luttinger liquids

TL;DR

This paper investigates how boundaries influence the one-particle spectra in Luttinger liquids, revealing boundary-enhanced spectral weight and a crossover from suppression to enhancement near the chemical potential.

Contribution

It provides a detailed analysis of boundary effects on spectra in Luttinger liquids, combining exact calculations with Hartree-Fock approximation insights.

Findings

Spectral weight is enhanced near the boundary over a large energy range.

Power law suppression occurs only very close to the chemical potential.

Hartree-Fock approximation captures some boundary effects.

Abstract

We calculate one-particle spectra for a variety of models of Luttinger liquids with open boundary conditions. For the repulsive Hubbard model the spectral weight close to the boundary is enhanced in a large energy range around the chemical potential. A power law suppression, previously predicted by bosonization, only occurs after a crossover at energies very close to the chemical potential. Our comparison with exact spectra shows that the effects of boundaries can partly be understood within the Hartree-Fock approximation.