NUMERICAL RENORMALIZATION-GROUP STUDY OF THE ONE-DIMENSIONAL T-J MODEL

The one-dimensional t-J model is investigated using the density-matrix renormalization-group (DMRG) method. We report a generalization of th e DMRG method to the case of arbitrary band filling and prove a theore m with respect to the reduced density matrix that accelerates the nume rical computation. Lastly, using the extended DMRG method, we present the ground-state electron momentum distribution, as well as spin- and charge-correlation functions. The 3k(F) anomaly of the momentum distri bution function discussed by Ogata and Shiba is shown to disappear as J increases. We also argue that there exists a density-independent J(c ) beyond which the system becomes an electron solid.