Abstract
We have studied correlation functions of the one-dimensional Hubbard model using the density-matrix numerical renormalization-group approach. The singularity exponents of the momentum distribution at k= and 3, as well as the power-law singularity of the spin-correlation function, are computed for large U (U/t=). The momentum-distribution exponent at k= and the spin-correlation exponent are in agreement with the analytic results, while the calculated exponent for momentum distribution at k=3 is about 3/4, which disagrees with the analytically predicted value 9/8. We also discuss several techniques for an accurate calculation of the correlation functions.
- Received 22 May 1995
DOI:https://doi.org/10.1103/PhysRevB.52.R5475
©1995 American Physical Society