Univ Gottingen Inst Theoret Phys Bunsenstr 9 D-37073 Gottingen Germany
Rhein Westfal Th Aachen Inst Theoret Phys C D-52056 Aachen Germany
Univ Munich Sekt Phys D-80333 Munich Germany
Max Planck Inst Festkorperforsch D-70506 Stuttgart Germany

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.

A reprint of this paper can be obtained from cond-mat in Germany or in the US

Physical Review B, 61 4393-4396, 2000.