GUTZWILLER CORRECTIONS ON MEAN-FIELD STATES OF THE T-J MODEL

This paper is devoted to a careful estimate, with a complete Gutzwiller projection on the whole lattice, of the effects of the particle number constraint on the Schwinger-boson slave-fermion mean-field states of the t-J model. Both the canted and the spiral states are considered. A detailed analysis is carried out at t/J = 2. We find specifically the following: (a) the canted state has the lower ground-state energies, (b) the system is long-range correlated at small dopings (delta < delta(c) congruent-to 0.07). For delta > delta(c), the spin-spin correlations have a finite range. (c) In the latter case, the energy is sensitive to a linear-Tpp in the bosonic spectrum. In addition, there exists a peculiar quasi-degeneracy associated with this behavior. Relations of these results to the copper-oxide superconductors are suggested.