SPECTRAL PROPERTIES OF THE ONE-DIMENSIONAL HUBBARD-MODEL

The spectral properties of the 1D Hubbard model are obtained from quan tum Monte Carlo simulations on large systems (N = 84) using the maximu m entropy method. It is shown for the first time that the one-particle excitations are characterized by dispersive cosinelike bands, in extr emely good agreement with slave-boson mean-field ones. Velocities for spin and charge excitations are obtained that lead to a conformal char ge c = 0.98 +/- 0.05. An exact sum rule for spin and charge excitation s is fulfilled accurately with deviations of at most 10% only around 2 k(F).